Authorities are investigating Thursday the discovery of a man's body at a beach in Oceanside.

Police said three Marines were driving along the beach when they noticed a man's body floating near the shore at around 11:30 p.m. Wednesday.

The men pulled the body out of the water and called police. Emergency responders arrived at the scene and administered CPR, but the man was pronounced dead.

Investigators said the man was fully clothed and did have identification on him.

Police have not released a name, but told 10News that the man is 51 years old and is possibly from Oceanside.

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