Perth traffic: Breakdown creates heavy traffic on busy stretch of Mitchell Freeway on Wednesday afternoon

A vehicle breakdown on a busy stretch of Mitchell Freeway northbound has banked up traffic as commuters head home on Wednesday evening.

The breakdown occurred on Mitchell Freeway before Reid Highway in Gwelup at 4.03pm.

The right lane and emergency lane was closed by the breakdown, and Incident Response is on the scene.

Traffic — which was already affected by peak hour numbers — is slow leading up to the site.

Main Roads has reminded drivers to exercise caution if driving in the area.

The breakdown has since been cleared.

A second breakdown shut the left lane of Mitchell Freeway further south earlier on Wednesday afternoon, near the construction-ridden intersection at Stephenson Avenue in Innaloo.

The left lane was been completely blocked which caused major congestion, and traffic remains slow leading up to the site.

The breakdown has since been cleared.