Pistorius has now joined his lawyers, and sits on the side of the court. He is sipping from a bottle of water and typed on his mobile phone.

He looks composed, but tired.

This is Pistorius' third day in the witness box. First two days were examination-in-chief, his barrister Mr Roux stepping him through his version of events leading up to the fatal shooting of Reeva Steenkamp in the early hours of Valentine's Day 2013.

Mr Roux likely has quite a few more questions to ask, but we expect Mr Nel will begin cross-examination today.

The chief prosecutor has a formidible reputation as a cross-examiner. He once kept an accused police chief answering questions for eight days, before eventually doing enough to secure a conviction.

Oscar arrives in court this morning following his dramatic day in the witness box. #Pistorius pic.twitter.com/UPrT48SKWN — lucy thornton (@lucethornton) April 9, 2014

Pistorius is now seated in the witness box, waiting motionlessly for the arrival of Judge Masipa.

As the judge enters the court, she is followed by her two assessors.

Just a reminder - there are no juries in South Africa, a judge sits alone with the assistance of two "assessors" who help her reach judgement.

Pistorius resumes his account at the point he enters the toilet cubicle.

"I checked to see if she was breathing, but she wasn't," he says.

He cradled her: "Her blood was running down on me."

He then attempted to pick her up. "Her arm was broken."

Pistorius' voice is cracking as he speaks. He is facing directly towards the judge.

"I couldn't pick her up. I was on my knees and on my feet and I was pulling her into the bathroom."

"I saw that her cell phone was in the toilet and I tried to call but it had a passcode that I couldn't access."

He ran back into the bedroom and grabbed both his phones.

Pistorius is demonstrating how he cradled his dying girlfriend in his arms, holding them in front of him in the witness box.

"I tried to pick Reeva up but I couldn't pick her up. I was scared I would hurt her more," Pistorius says, wiping away tears.

He says he doesn't remember calling his estate's security, but knows from call records he did.

Says he Netcare (like an ambulance service) who told him to take Reeva to the hospital immecalled diately. So he rang ambulance.

Once he'd dragged her from the toilet, Pistorius says he realised Reeva was "struggling to breathe".

He ran downstairs to open the front door, so he could carry her all the way downstairs without stopping.

As he reached bottom of the stairs with Reeva, he screamed at his neighbours to help him get her to the hospital, but estate manager Mr Stander told him to put Reeva down because ambulance was on its way. He did so.

"I had my fingers in her mouth trying to help her breathe, I had my hand on her hip trying to stop the bleeding."

Pistorius is crying.

"I just sat there, I felt helpless."

Pistorius is asked to explain the plastic bags at the scene. Says it was Stander's idea, to get something to tie to her wounds to help stem the bleeding.

Recalls a man walking into his house, who he now knows was a neighbour, Dr Stipp, and he tried to help him stem the bleeding.

"He didn't seem to know what he was doing, he seemed overwhelmed by the situation," he said.

The paramedics arrived a short time later and "asked for some space to work, so I stood up."

Pistorius puts his head down trying to stop the tears.

Long pause, as Pistorius' tears are preventing him from speaking.

"Reeva had already died whilst I was holding her, before the ambulance had arrived, so I knew there was nothing I could do," he said.

Mr Roux is trying to keep his client on track, asks if he at some stage went to the kitchen.

"I stepped a couple of metres away from them," he says, referring to the paramedics.

But a short time later, he was formally informed his girlfriend had died.

"The lady paramedic came to me and she said she'd like to inform me that Reeva has passed," Pistorius says.

Pistorius is weeping, and there are long pauses between his sentences.

"The paramedic asked me for identification," so he retrieved Reeva's handbag from upstairs.

He says he sat on the floor of the kitchen crying, before police arrived.

He says two police officers arrived and introduced themselves.

One, he recalls, was Colonel van Rensberg.

"Everytime I looked up there were more people in the house, more policemen. There were people going up and down the stairs. I was standing in the kitchen ... I asked one of the policeman if I could wash my hands because the smell of the blood was making me throw up."

He says Col van Rensburg allowed him to.

"I remember washing my hands, washing my chest, washing it off."

He sat in the pantry, against the washing machine.

"I couldn't look around the corner because every time I saw Reeva I was sick" - #OscarPistorius — Tom Steinfort (@tomsteinfort) April 9, 2014

Pistorius recalls being asked to go to the garage with a police officer, where photos were taken of him.

"I was in the garage for several hours," he says.

He says a police officer told him "I didn't have anything to worry about, he was there to look after me".

But then another officer placed him under arrest because he was the only other person in the house at the time of the shooting.

Pistorius says he was taken to hospital for tests.

Pistorius says categorically he was on his prosthetic legs when he used the cricket bat to try and beat down the door.

"I can barely stand on my stumps, let alone weild a cricket bat," he adds.

Mr Roux will shortly get him to use the bat to demonstrate how he did this. The cricket bat is back in court.

Roux is now working through the timeline, trying to connect it to what the neighbours told the court they'd heard, about shots and screams. — andrew harding (@BBCAndrewH) April 9, 2014

Pistorius says "it was about five minutes before I hit the door with the cricket bat."

This is consistent with witness neighbour Charl Johnson's evidence, he adds.

Pistorius' voice much stronger now he is analysing the evidence of others. He says there are "many many" pieces of evidence that support his version regarding the noises from the gun and then the cricket bat.

The athlete hitches his suit trousers and uses his right foot to "kick" the bathroom door in court. Reaches just above the handle.

He then grabs the cricket bat and shows how he struck the door. He swings twice, did not connect.

Before doing the demonstration, he tells the court it is hard to demonstrate in an impassive way what occurred in those fraught moments.

His actions did look incredibly stilted, like he was acting in a play, or for some kind of instruction video.

Resuming his seat, Mr Roux asks how hard he hit the door.

"I hit the door with all my might," he says.

We are now being shown an aerial photograph of the Silver Woods Estate, where Oscar Pistorius lived.

Mr Roux says he wants to go through evidence by other neighbours NOT called by the state.

He indicates his next door neighbour, whose home is metres from Oscar's.

That neighbour's statement to police makes reference to crying, not a woman screaming.

So we're now hearing about evidence given to police by witnesses the state declined to call in their case.

This evidence clearly was not helpful to state's case.

#oscarpistorius Interesting. Neighbours closest to OP dispute prosecution witnesses from further away who say they heard woman screaming. — Laurel Irving (@laurelirving7) April 9, 2014

Pistorius is more composed now. He knows this is crucial and we are away the emotive parts of his evidence.

Mr Roux quotes from other witness statements hearing crying but "not a woman screaming".

Oh dear, somebody's phone just rang. A member of the public gallery had not put their phone on silence.

Pause.

Judge Masipa will be cross.

Mr Roux now seeks to show Pistorius must have been on prostheses when the Stipps saw a figure walking in his bathroom. Too short otherwise.

"The only way they would have been able to see me was if I had my prosthetic legs on," the athlete says.

Mr Roux asks his client: "Did you ever intend to kill Reeva?

"I did not intend to kill Reeva, my lady, nor anyone else," Pistorius says clearly.

It looks like his evidence-in-chief is finished. Mr Roux asks for a short adjournment, and Team Pistorius gather for a mid-courtroom huddle.

We could be about to see the commencement of cross-examination. Chief prosecutor Gerrie Nel sits at the bar table, reading papers.

Court resumes and cross-examination starts in earnest.

Gerrie Nel: "Mr Pistoius, you were and still are one of the most regonisable faces in the world. You are a model for sportsmen and able-bodied sportsman all over the world, aren't you"

"I was, my lady, until that terrible mistake," Pistorius replies.

"You made a mistake? You killed a person! You killed Reeva Steenkamp. You shot and killed her," Mr Nel counters.

He tells him to take responsibility for his actions - he shot and killed Reeva Steenkamp, didn't you?

"I did, my lady."

Mr Nel tells him he has a responsibility.

Pistorius says he is here to tell the truth.

Prosecutor going for the jugular straight away: "Admit it? You shot and killed Reeva Steenkamp. Lets get to the truth" #OscarPistorius — Tom Steinfort (@tomsteinfort) April 9, 2014

Mr Nel turns to questioning Oscar Pistorius about footage allegedly showing him shooting a gun at a watermelon, and making reference to a "zombie stopper".

This footage has previously been aired on Sky News.

Pistorius says he has never heard the term "zombie stopper" but Mr Nel says he can show the video.

However Mr Roux is objecting, saying the evidence has not been presented in the state's case so can not now be brought.

Mr Nel says it's in the public domain and he is happy to take an adjournment to ensure the defence has seen it.

Mr Roux is complaining about an "ambush". But Mr Nel says he asked the witness if he wanted to see it, and Pistorius had replied yes.

Pistorius is sitting in the dock, staring straight ahead, clenching his jaw. Muscles visible across court.

#OscarPistorius In the video a voice which sounds like the runner's says the melon splits 'like a zombie stopper' — Alex Crawford (@AlexCrawfordSky) April 9, 2014

In that wild early exchange during which Mr Nel asks him about his "mistake", Pistorius added: "I am human I have many faults, I have sins, I believe I'm a sinner."

Mr Nel and Mr Roux still arguing about the admittance of the "zombie stopper" video.

While the court is in recess, Pistorius sits alone in the witness box. While he is under cross-examination, he is not allowed to consult with his legal team or discuss his evidence. He is the prosecution's witness.

The court clerk has told the court we will adjourn at 11.30am. Judge Masipa combining her decision-making with the morning tea break.

Pistorius stands beside the dock, sipping his water. He rubbed his face and speaks to his psychologist. He can't discuss his evidence.

Here's the video they're arguing about:

That's a break of half-an-hour, for those not on South African time.

We should resume shortly.

Judge came back on the bench briefly half an hour ago, says both counsel "have a point" and stood the matter down so the defence could view the video and "make further submissions".

If it's admitted, the "zombie stopper" video will prompt some very interesting questions from Mr Nel. It's a fascinating piece of evidence, casting Pistorius in a completely different light to the way he has been in court, and the way he would LIKE to be seen.

A recap of the opening exchange between the state's top prosecutor, Gerrie Nel, and Oscar Pistorius, as his cross-examination began.

Nel: Mr Pistorius, you were and still are one of the most recognised faces in the world, do you agree?

OP: I agree.

Nel: You are a model for sportsmen, even able-bodied sportsmen, all over the world?

OP: I think I was, my lady, until that terrible mistake...

Nel: A mistake? You made a mistake?

OP: Thats correct..

Nel: You killed a person, thats what you did, isn’t it? You killed Reeva Steenkamp, that's what you did?

OP: I made a mistake...

Nel: You're repeating it three times. What was your mistake?

OP: My mistake was that I took Reeva’s life.

Nel: You killed her, you shot and killed her. Wont you take responsibility for that?

OP: I did.

Nel: Then say it then, say yes, I killed, I shot and killed Reeva Steenkamp.

OP: I did, my lady.

Front row of the public gallery, behind the dock, sits Team Pistorius.

Cooler weather today has prompted Oscar's sister Aimee to wear a black long-sleeved polo-neck, while her brother Carl is wearing a rather courageous combination of a steel blue suit with a black waistcoat.

After that brief foray into fashion commentary, thankfully (for you) we're resuming with the evidence.

Pistorius is back in the witness box, after we think he and his lawyers viewed the video. Hard to believe they didn't know exactly what it was. Could not have missed it. Sky News ran it prominently around the globe.

Not to mention the Blade Runner is IN it, he was there, so knows what it's about.

Court officer calls silence in the court, and Judge Masipa returns to the bench.

Mr Roux is proposing a solution to the problem ... but we're not quite sure what it is.

Mr Roux is proposing a solution to the problem ... but we're not quite sure what it is.

Whatever it is, the video is played.

Nel asks him about it, and Pistorius says he has seen the video before.

He says he was at a shooting range, "I was shooting at the watermelon with a handgun."

"I think, in hindsight, I am upset to hear myself saying something like that," he said.

Pistorius at pains to stress that shooting wood and watermelon is not the same as shooting a human.

He says it wasn't him laughing, but admits they were his words.

Mr Nel puts it to the witness that the effect of Pistorius' bullets on the watermelon in the video had "exactly the same effect" on Reeva Steenkamp's brain.

As he says that, Mr Nel has a photo of Reeva's bloodied head put on the screen in full view, and Mr Nel urges Pistorius to look at it.

Pistorius breaks down, screaming and crying: "I remember I don't have to look at a picture."

Mr Nel says Pistorius doesn't want to look at it because he doesn't want to take responsibility for it.

Sobbing, Pistorius says: "I remember. I won't look at that picture. I remember!! I was THERE!!!"

Mr Roux stands immediatley and says Mr Nel has gone "too far".

The photo is removed from the big screens in court, but Pistorius sits with head in hands, sobbing uncontrollably.

Softening just a touch, Mr Nel asks if he can continue. Pistorius sits sobbing.

Adjournment.

Shooting a filthy and pained look at prosecutor, Aimee Pistorius rushes to the witness box to comfort her brother.

After hugging her for a while, he sits with his head in hands and continues to cry.

Aimee consults her aunt, who has joined her on that side of the courtroom.

Pistorius has been taken out of the courtroom, face crumbled and red.

We understand the graphic images of Ms Steenkamp's head, in which you can see parts of her exposed skull, hair matted with blood, have been broadcast live on TV.

Much debate in the courtroom about the state's shock-tactics. Reeva Steenkamp's mother has been in court and saw it too. She did not appear to become distressed. Presume she was warned ahead of time.

#OscarPistorius OP managed to say 'I am tormented by that...my fingers touched her head. I dont have to see a pic. I remember it — Alex Crawford (@AlexCrawfordSky) April 9, 2014

#OscarPistorius Pros lawyer now discussing showing the pic of Reeva's head with her mother June. — Laurel Irving (@laurelirving7) April 9, 2014

There were sharp gasps in the courtroom as the picture was shown. Everyone is in shock.

Nel is, without a doubt, trying to viciously strip away any concept that Pistorius is a victim in this. He wants him to confront what he did — Aislinn Laing (@Simmoa) April 9, 2014

Aimee Pistorius and her brother Carl embrace on the defence side of the court room. Pistorius was taken out of the courtroom by psychologist. Their whole family looks extremely distraught.

June Steenkamp looks composed, but red0eyed.

Think Mr Roux and Mr Nel have gone into Judge Masipa's chambers.

Shock and awe tactics from the prosecutor, undoubtedly.

Reeva's mother has told journos she understands why pic had to be shown. No doubt it was difficult to see her daughter like that. #Pistorius — Pumza Fihlani (@Pumza_Fihlani) April 9, 2014

Pistorius' psychologist now appears to be in floods of tears, sitting back in the front row with the Pistorius family.

Carl Pistorius hugs her protectively, as tissues are passed.

Speculation she's also a relative.

Everyone has resumed their seats, we wait for the judge.

We resume, and the prosecutor Nel returns to the "zombie video" line of questioning.

He asks what the purpose of the trip to the firing range.

"It was an afternoon out on the range with a group of friends, someone suggested we shoot the watermelons," he said.

Nel: You said (the words) "it's a lot softer than brain", didn't you?

OP: I did, my lady.

Nel says the inference from that statement is that you were seeing what it was like to shoot someone's brain.

OP says he "shot a watermelon and the comments he made afterwards were made "in reference to a zombie, not a human being".

Nel says he thinks Pistorius "shot that firearm to see what the effect would be" of shooting someone in the head.

Pistorius denies it, says it was about shooting watermelons and the comment (he now clearly regrets) was about zombies.

Nel asks if Pistorius' version of events is actual memory, or a reconstruction of everything he has heard and red.

Pistorius admits some of it is a reconstruction because he can't remember things about phone calls, what other people did etc.

"It's a mixture of what I remember ... a reconstruction. If I look at the time, I can't remember how much time (things took)."

Pistorius: From the time I went to sleep to when I took Reeva’s life there was no reconstruction.

Nel: Did you take into account other evidence to form our version for this period?

Pistorius says: "My version has never changed."

"State's case has changed many times, but (nothing they have come up with) have changed my version."

Pistorius says he wanted to give evidence at the bail hearing but he was advised by his lawyers not to, they said he wasn't mentally stable enough.

Mr Roux is on his feet again, objecting to lack of specificity of the question about reconstructing memory.

Earlier:

Nel attacks Pistorius, saying: You are arguing, you are not answering

Pistorius: I am sorry my lady

Nel: Sorry doesn't answer the question. Why?

We return to the questions.

Nel is letting Pistorius answer in his long-winded style. Suspect he is waiting to catch him out.

Suspect he is about to start highlighting differences between Pistorius' version at bail application, then in his "plea explanation" statement at the start of the trial, and in evidence.

I'm sure he hopes the shock tactics of earlier have left Pistorius distressed, confused and unable to keep his stories straight.

Nel talking about OP bringing in the fans.

Nel suggests it would not have been possible to hear the noise in the bathroom, from the balcony.

OP: No. I did not go onto balcony to fetch fans.

In his evidence yesterday, he said they were placed half-in, half-out of the balcony.

Nel cautions the witness not to think ok of other evidence, make speeches - says he must just answer the questions "or you're going to get into trouble".

This is a great cross-examination style.

Here we go - first attempt to catch him out.

Nel reads a portion of his statement to the bail application, in which Pistorius says he went out ON TO the balcony to bring in the fans. Now Pistorius says he didn't actually do that.

How many more will there be?

Pistorius is asked to read his bail statement over lunch, and Nel says we'll return to the fans afterwards.

In the meantime, Nel suggests Pistorius said during bail hearing he went 'onto balcony' and 'heard noise from balcony'.

Roux objects, saying that's not true.

But Nel re-reads segment, and Pistorius does too. He has put his dark-rimmed glasses on as he reads the transcript.

"Went onto the balcony" is the repeated refrain from the prosecutor.

Nel, reading: "I went ONTO the balcony..." That's not true?

Pistorius: "My lady, the fan was on the balcony."

Now we adjourn for an hour's lunch.

We are back underway in the Pretoria High Court, Mr Nel resuming his cross-examination.

Pistorius is not looking at Mr Nel, instead has his body turned towards Judge Masipa, and he addresses her.

We are focused on his first affidavit, which reads: "During the early morning hours of 14 February 2013, I woke up, went onto the balcony."

Pistorius says Barry Roux must have made a mistake, admits he wasn't present when the document was drawn up.

We move onto his plea explanation document, read at the start of the murder trial.

In it, Pistorius says the scene was "contaminated, tampered with".

Nel: Is that why you're pleading not guilty?

Pistorius: It's not the sole reason I pleaded not guilty. I pleaded not guilty because because what I'm accused of did not happen.

Mr Nel is fiercely demanding Pistorius explain to him where the scene was contaminated. What was it about it that bothers you the most?

OP: There were many things that were moved," before listing the cell phones, the cricket bat, the curtains, his gun.

"Let's take it slowly," Mr Nel says, beginning with the cell phones.

Mr Nel wants Pistorius to focus on the question, saying Pistorius clearly has "a lot of answers in your head" but that's beacuse they are the things he wants to get on record. Effectively warns him he must simply answer the question.

Mr Nel is now letting Pistorius talk about "scene contamination", tampering, people not wearing protective clothing.

"Are you saying the fans are tampered with?"

"Please give me the meaning of the word tampered."

Nel says when you change something on the scene with the intention to make it look different.

Can you just tell me how the fans were tampered with?

Pistorius says he remembers the fans were operating, so yes, the scene was tampered with. Says they were unplugged by police to plug in a cell phone.

Wonder if Mr Nel is aiming, by asking about all this, to portray Pistorius as blaming everyone else but himself. Not sure though. Just a guess.

Nel: "After that long argument, do you still not remember what I asked you? You are arguing ... you have thought of answers you want to give to the court."

Think this is going to go on for a while.

Mr Nel wants to know if Pistorius has consulted the experts.

He says no but admits he's sat in on meetings, "because I was only person there".

Pistorius mentions one mentions one expert who will be called by defence, otherwise tries to distance himself from nitty gritty of the evidence.

#OscarTrial Pistorius: when I leave court I’m tired, I don’t consult with them. I gave my version months ago. BB — Barry Bateman (@barrybateman) April 9, 2014

When answering, Pistorius uses the expression "we reworked my evidence" in relation to his case preparation, changing it quickly to "we worked with my evidence".

Mr Nel: You didn't want to use the word "reworked" your evidence?

OP: That was a mistake.

Mr Nel: "It's interesting that you did."

#OscarPistorius says he thinks things may have changed in photo. "That's brilliant" says Nel, with more menace than delight. — andrew harding (@BBCAndrewH) April 9, 2014

Pistorius clearly knows the evidence against him very well, and is well-prepared. He is talking a lot though, and that is not generally advised by defence lawyers. Shorter the answers, less room for cross-examiner to find holes, gaps, inconsistencies.

Mr Nel: "You said both fans were plugged into this extension cord. Now you say you're not sure. Why?"

"I'm fighting for my life," Pistorius says, adding it's not a big deal he can't remember the plug situation.

"It's not insignificant Mr. Pistorius. It will show that you are lying."

So we can now see where Mr Nel is going.

He's picking small holes and inconsistencies in Pistorius' evidence, discrediting him on small things so he can discredit him entirely.

"You are trying to adapt your evidence," he says.

Pistorius says he is not.

Mr Nel asks Pistorius why he mentioned only one fan, not the two he now talks about, in bail application.

Pistorius says he didn't put all the details in then.

He is speaking in a monotone, and has mentioned "the truth" a number of times in recent minutes.

"I have to tell the truth, I would rather place all the evidence in court now even if its not in my favour ... I know I will be taken apart for that. I can't change the truth," Pistorius says.

Nel says again: "You've got long answers. You're clearly rehearsed this. But you're not listening to the questions."

Mr Nel moves on, saying Pistorius "referred to this incident as an accident. What was that accident?"

Pistorius: I accidentally discharged my firearm believing there was an intruder in the house ... the discharge was accidental."

He says he "got a fright" from the noise in the toilet", believing somebody was coming to attack him and Ms Steenkamp.

Pistorius: I never intended to shoot anyone. I wasn't meaning to shoot anyone. Went to bathroom to put myself between danger and Reeva.

"I shot out of fear."

Mr Nel asks if he is feeling okay, and Pistorius replies no.

"My life is on the line," he says.

"I never intended to kill anyone," saying he just fired out of fear.

"I had my finger on the trigger, it was an accident what happened. I agree with that. I didn't intend to shoot anyone. I fired my firearm before I could think, before I even had a moment to comprehend what was happening."

Mr Nel asks if it was the only option - a question many have asked.

"I didn't have time to think," he replies.

"It's easy for me to sit back now, to think what I could hae done ... but at that time I didn't, I had to deal with the situation I found myself in, I beleived I was going to be attacked and my life was in danger," he says.

This line of questioning is crucial - Pistorius is adamant he did not mean to shoot anyone, because to admit he shot with an intention to kill would almost certainly land him with a conviction for culpable homicide, at the very least.

State has argued that - even if #OscarPistorius believed Reeva was intruder - he meant to kill "intruder", is guilty of murder @eNCAnews — Karyn Maughan (@karynmaughan) April 9, 2014

Again, Pistorius says his "life is on the line."

Mr Nel seizes on this, saying "Reeva doesn't have a life because of what you've done. So please give us the truth."

Pistorius puts his head down, and appears to be trying not to cry.

Mr Nel turns to bail application again, asking why Pistorius shot at the door then, when today he says he never did.

Prosecutor: You can't get away Mr Pistorius I asked you if you fired at door (earlier) and you said no."

After a long reply, Mr Nel says: "Are you done sir?"

"Yes, my lady", the Olympian replies.

And we adjourn for the day.

Back tomorrow, same time - 9.30am.

Cross-examination likely not completed for some time yet...

#OscarPistorius sits with his family, rubs his head. Looks exhausted, frustrated. — Nastasya Tay (@NastasyaTay) April 9, 2014