Firefighters from across Southland who were called to an explosion at Dongwha New Zealand's plant in Mataura at 4.30pm are preparing to leave the scene.
Southland fire chief Bruce Stubbs said the cause of the fire was not known. However, it was believed to be linked to a separate callout in the plant's press room at 12.25pm today.
"It appears that there may have been some hotspots in another part that we weren't aware of," Mr Stubbs said.
Thermal cameras were being used to ensure all the hotspots from the second fire had been put out, he said.
He expected appliances to begin leaving the scene in about 30 minutes.
Earlier today a Fire Service spokesman said appliances from Gore, Mataura, Edendale, Wyndham and Invercargill had been called to the MDF factory after a report of an explosion and `"multiple seats of fire'' at the MDF factory,
There had been no reports of injury.
A Mataura resident said there were lots of sirens but they did not hear the explosion.
In November last year the plant's energy centre went up in flames and in April this year an explosion and minor fire also prompted a fire callout.