New details are emerging about a tour boat accident in Branson, Missouri, that left 17 dead including the driver, children and nine members of one family. Video of the boat’s final moments show it struggling to stay afloat.

A severe thunderstorm whipped up the wind, and waves that battered the duck boat, which quickly took on water. Horrified passengers on a nearby boat called for help as the duck boat sank in Table Rock Lake, some 80 feet deep, with 31 people on board.

Roger Carpenter, who works at the marina, jumped into a boat to help with the rescue.

“We get out there, we don’t see anything. All we see is a debris field, life jackets floating, life rings floating. Nobody around. It was really eerie,” he said.

Thirteen bodies were recovered Thursday night and four more Friday morning. Fourteen survived, including the captain, who had the presence of mind to release the canopy, allowing some to escape. By law, the duck boat has life jackets on board, but passengers aren’t required to wear them.

At 6:32 p.m., about 40 minutes before the boat sank, the National Weather Service issued a severe thunderstorm warning for winds that would eventually reach 70 mph. But a severe thunderstorm watch had been in effect for the area since 11:20 a.m. Thursday. By 7:09 p.m., 911 received the first call for help.

With the storm warning in effect, it’s unclear why the duck boat, and another that made it back safely, were out on the lake.

Jim Pettison, Jr., president of parent company Ripley Entertainment, said nothing like this has ever happened in the business’ 47-year history.

As for the survivors, four patients were still in the hospital Friday evening, including two adults in critical condition.