Rural Fire Service forensic investigators have interviewed a 'person of interest' as the battle to contain the Macleay River fire enters its 15th day.
RFS investigators from Kempsey and Coffs Harbour arrived yesterday to investigate the possible cause of the blaze in the Oxley Wild Rivers National Park which has since burnt out 33,160 hectares of bush and pasture land.
RFS Public Liason Officer Inspector Brett Loughlin said all major fires were investigated as a matter of cause and investigations were ongoing.
Around 80 firefighters from the NSW RFS, FRNSW and NPWS, supported by five aircraft and four bulldozers are fighting the fire, which has a 247 kilometre perimeter.
Ember attack on properties around the Lower Creek area were reported yesterday but Inspector Loughlin said that firefighters were working with local landholders to protect at-risk homes.
Inspector Loughlin said that good containment lines had been established by fire crews in the last 24 hours and today "aerial incendiary" work by helicopter would be carried out on the south western side of the blaze.
"It's still an active fire but we're starting to get a handle on it," Inspector Loughlin said.
The Macleay River Fire is the culmination of the Freds Creek and Georges Junction Fires that had merged last weekend.
The fire is burning in the vicinity of the Comara, Georges Junction, Five Day Creek, Lower Creek, Blanches Creek and Smith Creek areas.
Another fire burning near Guyra, has been contained.
The Mulligans fire, which has burnt out 3207 hectares near the Guy Fawkes National Park has been burning since Saturday.