A caller reported the man had run into the water just after 5:20 a.m. and had not been seen since.
Police, along with the FDNY, responded to Brighton 6th Street and began their search.
Firefighters put a diver in the water, while flying a drone overhead, as they searched for nearly an hour.
An NYPD helicopter scanned the water from above. Both NYPD and FDNY also had boats in the water.
With no victim located, FDNY pulled the diver out of the water at around 6:30 a.m.
Lifeguards are not on duty until 10 a.m. Swimming had not been permitted on city beaches for the past four days due to rip current concerns, but the red flags were lifted Wednesday morning.
Ocean conditions have been at their calmest in days since Ernesto-fueled rough waters in the area.
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