A 3.5m great white shark has been spotted off a Falcon beach, near where the Mandurah Pro surfing competition is taking place.
The shark was sighted by a member of the public about 500m off Avalon Beach around 8am on Monday.
Surfing Western Australian Events Manager Justin Majeks said despite the sighting, the Mandurah Pro is still going ahead.
"We were made aware by some fishermen early this morning that they spotted a shark at the back of our competition area," he said.
"We've got a good safety protocol in place.
"We've got a drone in the air and water safety officers on deck too and we haven't seen or detected anything else."
The Mandurah Pro is a four-day surfing event which finishes on Tuesday.
Public report 3.5m white shark sighted 08:00hrs 15/10, Avalon Beach, Mandurah 500m offshore , 200m north of Avalon beach..
— Surf Life Saving WA (@SLSWA) October 15, 2018
Early voting for Secret Harbour by-election begins Monday
Welfare concerns for missing Swedish national last seen in Warnbro
Wanted man last seen in Golden Bay
Passenger critically injured in West Pinjarra crash
Unregistered painter fined for requesting hefty deposit from Singleton homeowner and not doing the job
Police hunt driver following dangerous Baldivis pursuit
Welfare concerns for boy last seen at Port Kennedy skate park
Rubbish truck catches fire in Baldivis
Driver injured in bus crash in Rockingham