A crash on Leach Highway has caused more headaches for Perth motorists, just as a string of earlier peak-hour crashes were cleared.

The latest crash happened on Leach Highway southbound just after Albany Highway in Cannington.

Main Roads WA said the right lane was blocked by towing services, with traffic slow on approach.

Motorists have been urged to merge safely and expect delays while the scene is cleared.

It comes after a chaotic morning on Perth roads with crashes at Greenwood, Langford and Bateman, along with debris on Mitchell Freeway at Heathridge, all cleared.

Despite this, traffic remains heavy in several areas as congestion slowly eases.