The Coast Guard and other agencies were searching for 30-year-old Neil Gibbons, a native of Ireland, in the waters off Long Beach after he was last seen swimming with friends in the vicinity of Long Beach Boulevard at 2 a.m.
Three officers jumped into the water to rescue a swimmer, who told them the other person was missing.
The group of friends made it safely to shore with the exception of the missing man.
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"The water was very bad last night," Long Beach Patrol Chief Paul Gillespie said. "No one should've gone in last night, especially with no lifeguards there. Again. Which, we have that problem, unfortunately."
During the rescue effort, searchers covered more than 650 miles for a total of 29 hours, the Coast Guard said.
This new search came just one day after a body was found in the water, with investigators working to figure out if it is a 10-year-old boy who vanished during a swim last week.
Nassau County marine officers discovered the body off the shore of Lincoln Boulevard Beach Sunday afternoon, five beaches east of where Ramell McRae, Jr., disappeared.
The boy went missing while swimming with his 11-year-old brother.
The Coast Guard urges swimmers to always swim in areas where lifeguards are present.
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