Freeway crash: Mitchell Freeway reopened power line blocked lanes

UPDATE: The Mitchell Freeway has been reopened after a crash caused a power pole to fall onto the road affecting all lanes.

The crash happened about 9.30am on Monday in the southbound lanes near the Hepburn Avenue exit in Greenwood.

The incident caused traffic chaos with cars bumper-to-bumper all the way back to Whitfords Avenue.

Main Roads WA had issued an alert warning motorists to avoid the area.

An earlier crash along the busy freeway in Joondalup also affected peak hour traffic.

That crash happened just before 7am in Joondalup, prompting traffic management to block the left lane along the southbound lanes near Ocean Reef Road.

Traffic was heavy in the area for just under an hour, with cars backed up to Hodges Drive.

All lanes were reopened before 8am.