MOTORISTS hoping to get onto the Kwinana Freeway southbound from Roe Highway are in for lengthy delays after truck jackknifed on Monday afternoon.
According to a witness, the truck jackknifed and tipped its trailer on the highway around 1.45pm in Jandakot on approach to the freeway.
As a result, lanes are blocked at the scene with Main Roads making the decision to close Roe Highway westbound.
Detours are in place through Karel Avenue and Berrigan Drive, but there are long delays.
Traffic is already banked back past the South Street exit in Leeming.
Work is now under way to clear the trailer from the highway, but it remains closed for at least another hour.
According to police, the truck driver did not require medical assistance.