A section of the northbound lanes of the Forrest Highway was closed on Friday morning after a two-truck collision spilled at least 200 litres of diesel onto the road.
The collision happened in the northbound lanes of Forrest Highway, between Greenlands and Pinjarra roads, about 11.30am on Friday.
Traffic heading north was diverted from the highway at Greenlands Road.
It is estimated the section of road will be closed for at least two hours.
St John Ambulance, local firefighters and Main Roads were called to the scene.
The condition of the vehicles' occupants is unknown.
A spokesperson from Police Media said there was debris on the road.
More to come.
