A crash on the Mandurah Estuary Bridge in Halls Head caused massive traffic delays on Wednesday morning.
The crash, believed to involve a bus and three cars, happened just before 9am.
A St John Ambulance spokesperson said a woman in her 20s and a man in his 50s have both been conveyed to Peel Health Campus with non life-threatening injuries.
The Mandurah Estuary Bridge has since reopened.

Bushfire readiness takes centre stage at City of Kwinana's free Summer Sounds festival
WA Open Golf Championship to tee off at Secret Harbour Golf Links
Halls Head named WA's most persistent storm damage hotspot
Four illegal e-bikes to be crushed after police crackdown in Halls Head, Falcon
Aboriginal jobs and careers expo to attract 1000 attendees in Rockingham
Firefighters attend Lakelands home after reports of thick smoke
WA Government to ban screen use for younger students as part of six-month trial
Singleton General Store shutdown over illicit tobacco, vape sales
Concerns for missing Bertram woman
