Firefighters say they are likely to be in place for the rest of the day at the scene of a warehouse blaze in Bicester.
More than 45 firefighters were called to the incident at the Polestar Group premises in the Chaucer industrial estate just before 1am.
The fire reportedly started in a gas-driven forklift truck being used in the warehouse at the time, and quickly spread to the contents of the building.
The incident commander, Station Manager Paul Molloy, said firefighters had moved quickly to control the fire to stop it spreading to neighbouring buildings.
He said there had been no injuries to employees or firefighers.
Employees had initially tried to tackle the fire themselves before the firefighters arrived.
At the height of the fire, more than 45 firefighters with five appliances and four specialist vehicles from Oxfordshire and Bucks attended.
This morning, workers were busy removing goods from neighbouring buildings while firefighters continued to monitor and damp down the fire.
The large temporary building where the fire had started was severely damaged, and Station Manager Molloy said a structural engineer was due to inspect the premises. The building might have to be demolished, Station Manager Molloy said.
Two crews attended from Bicester, one from Rewley Road in Oxford, Kidlington, Waddesdon, Woodstock and Eynsham as well as South Central Ambulance Service and Thames Valley Police.
They were at the scene throughout the night to extinguish the fire.
A full investigation into the cause of the fire is underway.
A member of staff at Polestar said the firm would not be issuing a statement over the fire today.