Six teenagers from at least two families drowned in the Red River in northwest Louisiana after they stepped off a ledge from shallow water into a 18-foot sinkhole Monday, fire officials said.

Shreveport Fire Chief Brian Crawford told the Shreveport Times that the victims, aged 13 to 18, had drowned while trying to save each other. Only one, a 14-year-old, was rescued.

Emergency crews on both sides of the river responded to reports of a single person drowning before 6:30 p.m., just south of the area in Charles and Marie Hamel Memorial Park. It took fire officials about 10 minutes to locate the sinkhole, and that's when they learned there were multiple victims.

Dive teams from Shreveport and Bossier fire departments, as well as members of the Caddo Parish sheriff's office, searched the water about an hour before recovering the first body. By 10:30 p.m., all the bodies were recovered.

None could swim

Marilyn Robinson, a friend of the families, watched helplessly as the children, five boys and a girl, went under, the Times reported.

"None of us could swim," the 38-year-old told the newspaper. "They were yelling 'help me, help me. Somebody please help me.' It was nothing I could do but watch them drown one by one."

With tears rolling down her face, Louise Edwards, another witness, added: "It was hard watching them and not being able to help. Some people tried to jump in, but they were already gone. It's like a nightmare. Lord please help us, please."

Robinson said a group of family and friends, including about 20 children, had been out at a sandbar to barbecue and enjoy the water. She said they were familiar with the area, the Times reported.

Crawford was clearly affected by the tragedy as he announced the deaths.

"Unfortunately, I'm afraid, and it's with a heavy heart, to report that we have pulled so far (six) bodies from the river," he said, according to the Times. "I can honestly say that in my 26 years of service I've never seen anything of this magnitude. And I hope I never see it again.

"It's truly catastrophic and I can only imagine the effect it has on the families," he added.

Unfamiliar area

The teens had started playing in the area that they knew.

"One child ventured off into an area that he was unfamiliar with, and some of the other children had gone off with him," Crawford told the Times. "They went into the vicinity of an 18-foot sinkhole."

"And once one started toppling into that sinkhole grabbing a hold of another, trying to save another, eventually seven were pulled into the hole," he added.

Assistant fire chief Fred Sanders said it was believed the dead included three brothers from one family and a sister and two brothers from another.

The families were in recreational area of the Red River, Sanders said. The park is a popular picnic and fishing area and some people go wading.

"It's devastating," Sanders said. "To my knowledge the city has never experienced an incident of this magnitude. Unfortunately, neither the children nor the adults could swim."

The Times reported that only one life jacket was available.

Shreveport Mayor Cedric Glover, members of the City Council and Caddo Schools Superintendent Dr. Gerald Dawkins arrived at the scene with rescue crews.

Area ministers and city officials helped console grief-stricken relatives and friends as they gathered at the park and waited to receive updates from authorities.

The area where the teens drowned is not a public beach, and trenches had actually been dug to make it more difficult for people to enter the water, Glover said.

"The river's condition today, it has a little bit of current," said Donna Jackson with Caddo sheriff's marine unit Monday.

"It's like any other waterway or lake. If you don't know what's out there, the dangers like the drop off the jetty, this sort of thing can happen," she added. "We've been very fortunate in the last few years; everything has gone well. Unfortunately, this happened today."