A three-metre shark has been spotted off Secret Harbour Beach.
The Surf Life Saving helicopter sighted the shark around 11.25am on Thursday about 70-metres offshore.
It is tracking north.
Beachgoers are advised to be extra vigilant when entering the water.
SLS Westpac Heli report 3m unknown sp. shark sighted 11:24hrs 13/04, Secret Harbour Beach, north of Mandurah 70m offshore , TRACKING NORTH.
— Surf Life Saving WA (@SLSWA) April 13, 2017
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