A body has been found in the search for a man who disappeared in crocodile-infested waters after a late night swim with friends.

Brendon Doherty, 55, jumped off the Channel Island Bridge, near Wickham in Darwin’s southeast, around 9.40pm on Friday.

He reportedly spent several minutes laughing and being active in the water before he started drifting away.

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Emergency services were called just after 9.30pm 9.42pm and rescuers rushed to the area to search for him.

Police have been told Doherty was unable to swim back to shore, despite his friends’ attempts to encourage him.

Witnesses watched him for about two minutes before losing sight of him.

He was last seen in the middle of the channel, drifting toward Darwin City in strong tidal currents.

A huge multi-agency search of the Darwin Harbour on Friday night went until the early hours of Saturday morning, with rescue resources redeployed again later that day.

A body was spotted in the water near East Arm Wharf about 11.30am on Saturday.

East Arm Wharf is about roughly 10km northeast of Channel Island Bridge, around Wickham Point.

An NT Police vessel recovered the body and the man was declared dead.

“The body recovered matches the description of the person who jumped off Channel Island Bridge,” police said.

A report will be prepared for the coroner.

Surf Life Saving members, NT Emergency Service volunteers, Crocodile Management, the Port Authority, and NT Police members were all involved in the search, with helicopters and police boats deployed for the operation.

“The NT Police would like to thank all supporting agencies and members of the public who may have assisted in conducting a search of Darwin Harbour,” police said.

Channel Island, about a half-an-hour drive from Darwin’s CBD, is a scenic coastal reserve and popular fishing and camping area.

Visitors are urged to stay out of the water as the area is a known saltwater crocodile and box jellyfish habitat.