The search entered its second day Tuesday for a man who disappeared while swimming in the Nissequogue River near the Kings Park Bluff.

Authorities say the man was last seen around 8 p.m. Monday struggling in the water. Moments later, he vanished, prompting a multiagency rescue effort.

On Tuesday, rescue boats returned to the water. Agencies taking part in the search include Suffolk County police, the Town of Smithtown Harbormaster, multiple local fire departments and the U.S. Coast Guard.

Divers were deployed to search underwater, and a police helicopter conducted an aerial sweep of the area. Officers with the Marine Bureau also used side-scan sonar in hopes of locating the missing swimmer.

Despite the ongoing search, no signs of the man have been found as of Tuesday afternoon.

Local residents, including seasoned fisherman Ryan Medwig, of St. James, say the waters near the bluff can be deceptively dangerous.

“I’m a commercial fisherman for 35 years. I’ve seen a lot of tragic things happen down here,” Medwig said. “People need to be aware the currents are very strong here.”