Police divers have located the body of a Perth man who drowned at a popular lakeside campground.

John Rashidi and his brother were swimming with a friend about 20 metres from the shore at Stockton Lake, seven kilometres east of Collie, on Monday afternoon when he got into trouble.

Witnesses said the 22-year-old was on an inflatable pool toy when he fell off and began to struggle.

John Rashidi was swimming with his brother and a friend when he fell off a pool toy and disappeared under the lake's surface.

John Rashidi was swimming with his brother and a friend when he fell off a pool toy and disappeared under the lake's surface.

John Rashidi drowned while swimming at a lake in Collie, WA on Monday afternoon.

John Rashidi drowned while swimming at a lake in Collie, WA on Monday afternoon.

“When he went to grab it, it kept floating away from him so he went out a bit further to grab it but it was out of his depth, then he yelled out ‘I’m in trouble,’” witness Reg Crosby told 9News.

Divers located Mr Rashidi’s body just after 1pm today.

“It appears that he has gotten into difficulty in the deeper water and then gone under the surface,” Senior Sergeant Heath Soutar told 9News.

Police divers had trouble locating the drowned man's body in Stockton Lake, but found him just before 1pm today.

Police divers had trouble locating the drowned man's body in Stockton Lake, but found him just before 1pm today.

A large group of Mr Rashidi’s family accompanied police to the location in the hope that his body would be found. They are questioning why there were no lifeguards on duty at the campgrounds such a busy time of the year.

Police praised three young women who swam out to where Mr Rashidi was last seen and attempted to help him.

The lake remains closed while police recover the body.

© Nine Digital Pty Ltd 2019

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