Suffolk detectives are investigating the apparent drowning of a man found in the Great South Bay Tuesday afternoon.

Marine Bureau officers responded to Grass Island, located approximately a mile south of Fire Island Avenue, at around 2:40 p.m. after a 911 call reported someone floating in the water.

An adult male was found unresponsive. He was pulled from the water and pronounced dead.

The man was transported to the Office of the Suffolk County Medical Examiner where an autopsy will be performed to identify the victim.

Detectives are asking anyone with information to call the Homicide Squad at 631-852-6392.