The alarm was raised earlier on Thursday morning.
Around 9am on Thursday a surfer at Guillotines Surf Break, three kilometres north of Cowaramup Bay in the Shire of Augusta Margaret River, reported coming into contact with a shark.
He said he was surfing around 80 metres offshore when he felt a bump from his surfboard by a shark. The man described the shark as white in colour and between 2.5 to 3 metres in length.
Water Police were contacted around 10am with investigations to follow. The surfer did not receive any injuries.
Surf Life Saving WA said to take extra caution if visiting the Guillotines and adhere to any beach closure signs.
Officers from the Department of Biodiversity Conservation and Attraction are attending the area and preparing signage.
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