UPDATE 1.25PM: The Dawson Highway, between Calliope and Biloela, is now open to all vehicles but with only one lane after a diesel spill yesterday afternoon.
UPDATE 8.40am: The Dawson Highway, between Calliope and Biloela, is still closed to heavy vehicles after a diesel spill yesterday afternoon.
Police anticipate the highway to be closed to heavy vehicles, not passenger vehicles, for at least 24 hours.
Motorists can call 13 19 40 for updates.
UPDATE 8.45pm: The diesel from petrol carrier involved in a truck crash on the Dawson Hwy this afternoon has been decanted.
A Queensland Fire and Rescue Service spokeswoman said the diesel had been placed into another truck.
She said fire crews and other emergency service personnel were still at the scene cleaning up.
BREAKING 6pm: Police are at the scene of a serious traffic crash which has closed the Dawson Highway near Biloela.
Preliminary information suggests around 4.30pm, a truck and a tanker collided, causing diesel to spill for 2.5 kilometres along the highway.
Due to the extent of the spillage, the highway has been closed roughly 20 kilometres east of Biloela.
Diversions are currently in place for light vehicles along Old Coal Road. No diversions are possible for heavy traffic.
No one is believed to have been injured in the incident.