Scarborough and Brighton beaches are closed after a 2.5m shark was spotted off the beach.
Surf Life Saving WA tweeted at 12.06pm that the shark was spotted 150m offshore from the Westpac Rescue Helicopter south of the Scarborough patrolled area.
The species of shark was not known.
City of Stirling Beach Inspector has closed Scarborough and Brighton beaches.
It follows a tiger shark sighting at Dunsborough around 9am this morning.
Surf Life Saving WA also reported that lifesavers and an ambulance had been called to Cottesloe Beach for a male patient with a suspected spinal injury.