Police discovered the lab on Wednesday afternoon after they executed a search warrant at a Granville Street home.

A .22-calibre rifle and air rifle were found at the house, as well as cannabis seeds and about 740g of cannabis.

The house was evacuated and shut down when police stumbled across glassware they allege was used to make amphetamines.

Officers arrested 40-year-old Craig Adamson at the house and charged him with supplying a prohibited drug, manufacturing a prohibited drug and not keeping firearms safely.

He was refused bail at an appearance in Inverell Local Court yesterday and will reappear on Thursday.

Senior police said the drug investigation began when a 39-year-old man was allegedly found with cannabis in his possession after leaving the house on Wednesday.

The man was charged with drug possession and will appear in court on July 26.

Officers applied for and were granted a search warrant, raiding the house about 3pm on Wednesday.

Inverell police duty officer, Inspector Rowan O’Brien, said chemical operations officers arrived in town late yesterday afternoon and were expected to conduct a preliminary inspection of the house and shed before beginning their examinations today.

Drug, firearm and explosives dogs are expected to be on-site also.

Inspector O’Brien said the drug lab was not linked to two similar labs found in Inverell rental properties last year.

“The arrest was just two local officers acting on intelligence,” he said.

“They were able to obtain enough information to apply for the search warrant and it obviously rolled on from there.”

Inspector O’Brien said police weren’t sure if other drugs were on the property because the search had been abandoned due to the “likelihood of volatile chemicals” there.