Emergency crews were called to Denhams Beach, south of Batemans Bay, to search for a diver reported missing about 2.45pm.

The Moruya-based Lifesaver 23 rescue helicopter was sent to assist in the search and found the man floating unconscious in the water.

He was winched aboard the chopper and taken to the beach where CPR commenced, however efforts to revive him were unsuccessful.

It was not immediately clear if the victim was a skin diver or scuba diver.

Police and local life guards were also at the scene.

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