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.
Southern suburbs electrician claims $1.8 million Lotto win
Works continue on Pinjarra's Munday Avenue extension
Halls Head support worker charged with historic child sex offences
Severe thunderstorm warning cancelled for Mandurah, Bunbury
Fortnightly red bin collections to remain in the City of Rockingham after council rejects motion
Rate rises on the way for Rockingham, Mandurah ratepayers
Harvey Police call on witnesses to serious crash
Men allegedly under the influence of alcohol when boat crashed under Mandurah Estuary Bridge
Works underway on 26 new social homes in Kwinana