Three young children were rescued after a boat capsized on the Pearl River Saturday, but the operator of the boat died and search and rescue crews were still searching for the children’s mother, 31-year-old Jonie Morgan of Folsom, Sunday afternoon.

The body of 41-year-old Terry O’Keefe Jr., who was operating the 14-foot aluminum flatboat, was discovered by searchers at about 8 a.m. Sunday, the Department of Wildlife and Fisheries, the lead agency in the investigation, said in a news release.

O’Keefe was also from Folsom.

The children, a 4-year-old girl and boys ages 6 and 8, were treated for hypothermia but were otherwise uninjured.

The Sheriff’s Office and Wildlife and Fisheries got a call at about 5:30 p.m. Saturday that a boat had capsized near Lock No. 3 on the Pearl River. Agents believe that the vessel turned over when it went over the lock and O’Keefe wasn’t able to start the boat.

A 16-year-old boy who came up on the scene saw the two boys and their mother in the water and went to their aid. His boat also capsized, but he was able to grab the children and their mother, according to the agency. He lost hold of Morgan where her shirt tore, and she did not resurface.

WWL-TV spoke to the teenager, Leyton Page, who said he forgot his hunting gear at his camp site, which forced him to go back. That's when he ran into the accident scene of the capsized boat and jumped into action:

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A fisherman on the bank went into the water and brought the two boys and the teenager to safely to shore.

The 4-year-old girl was found after she popped out from under the capsized boat, where she had been stuck for 30 minutes but was able to breathe.

All three children were wearing personal flotation devices, but investigators do not believe that the adults were.

Follow Sara Pagones on Twitter at @spagonesadvocat.