Authorities are investigating reports a major factory fire at Ipswich, west of Brisbane, may have been deliberately lit.
The fire at Viscount Plastics on Cobalt Street, in Carole Park, broke out just after 3pm (AEST) on Sunday, causing about $500,000 worth of damage.
Firefighters say the blaze spread and they were unable to save several neighbouring buildings.
The factory fire was brought under control on Sunday night.
Brisbane Fire Chief Steve Holland says fire crews had been sent from Ipswich, Brisbane and Logan City.
The factory makes rigid plastic containers, food packaging, and lubricant packaging.
Fire crews had earlier warned locals who could smell smoke to keep windows and doors closed, but the smoke has dissipated.
Earlier there were reports of explosions at the site of the fire.
Local councillor Paul Tully said thick black smoke rose hundreds of metres into the air.
“There’s very thick acrid plumes of smoke, but just when you think it might be dying down a little the plumes just come back up a little bit and into the sky towards Camira,” he said earlier on Sunday evening.