A man has been attacked by a shark at Pyramids Beach in Dawesville near Mandurah, suffering deep cuts to his foot, reports say.
The man, believed to be 18 years old, was attacked at the beach south of Perth about 5:10pm on Wednesday, ABC News Perth reported.
The shark was spotted about 4:50pm and Surf Life Saving WA was notified of the attack 20 minutes later.
The man was taken by ambulance to Peel Health Campus with a deep laceration to his foot where he remained on Wednesday evening in a stable condition.
The attack near Mandurah marks the first shark attack on West Australian beaches in 2015.
The Department of Fisheries said the species of shark was not known but it was investigating the incident.
Pyramid Beach has been closed until Thursday morning, when the agency will reassess the situation.