Firefighters are on the scene of a diesel spill in Oakford.
It happened on Hopkinson Road near the intersection of Abernethy Road just before 11am on Monday.
"Diesel has spilled on the road after a traffic accident involving a truck," a DFES spokesperson said.
Motorists have been advised to avoid the area.
A number of roads have been closed including Hopkinson Road between Thomas Street and Abernethy Road.
"As a precautionary measure, people in the area should remain inside, out of the smoke or fumes, with doors and windows closed. Air conditioners should also be switched off."
18-year-old male from Lakelands charged over incident in Pinjarra
BREAKING: Reports of a man armed with a firearm in the Pinjarra area
Hayden Ballantyne signs with Rockingham Rams
Mayor reassures community that 'no decision has been made' to close 4WD access at Tim's Thicket, White Hills beaches
DBCA 'sick and tired' of illegal access to Port Kennedy Scientific Park
Mandurah homeless camp goes up in flames
Dawesville community shocked after kangaroo deliberately mowed down
Teens armed with knife, scooter charged over Rockingham Shopping Centre fight
Mandurah private school teacher charged with alleged sexual abuse of male student