Thirteen victims already have been found. Eyewitness video showed the craft, which travels on land and water, taking on water as waves lashed at its sides. He described the rescue effort as "outstanding".
The operators of Maine Duck Tours say they are reviewing all safety and weather policies following a duck boat accident in Missouri that killed 17 people. The dive teams halted their operations around 11 p.m. CT, and will resume their search Friday morning, Rader said. He wrote Friday on Twitter, "Such a tragedy, such a great loss".
In a short video taken by Malaske from a dock, the duck boat can be seen wallowing through the choppy, wind-whipped lake, with water only inches from its windows. Lester was on a nearby boat.
"We have a clear line of sight to both across the water", Zerby said.
Lester's boyfriend, Trent Behr, said they saw a woman in the water and helped to pull her into the boat. EMTs arrived before he could administer CPR, he said.
Authorities said the dead include children, possibly as young as 1 year old, and elderly tourists.
Rader would not comment on the ages of the victims, but Missouri State Highway Patrol Sgt. Jason Pace told the St. Louis Post-Dispatch that they range from the very young to the elderly.
Branson is about 200 miles southeast of Kansas City, and is considered a major family vacation destination.
On Friday morning, Missouri Governor Mike Parson said of the tragic situation, "Our thoughts and prayers right now are with these family members".
Rescue personnel work after an amphibious "duck boat" capsized and sank, at Table Rock Lake near Branson, Stone County, Missouri on Friday in this still image obtained from a video on social media. "I believe it was caused by weather, yes".
At the time, he said, the lake seemed calm, and no one was anxious about the weather.
The National Weather Service had issued a severe thunderstorm warning for the Branson area Thursday evening. The Coast Guard and National Transportation Safety Board are investigating.
The Ride the Ducks Branson duck boat capsized and sank on Table Rock Lake near Branson during a storm that "came out of nowhere", said Jim Pattison Jr., president of the business's parent company.
Cox said his employees were able to save two people and recovered three bodies - none of whom were children. Seven people were taken to the hospital; two of the wounded are in critical condition, according to a local hospital.
"Obviously we shouldn't be out there in severe weather", Pattison said.
At that office meteorologists had clocked winds at 74 miles per hour (119 kilometers per hour), issuing a warning to the area at approximately 6:30 pm.
Strong winds were reported in the area around 7 p. m.
Four people were still unaccounted for early Friday, but Rader said in an update later there are no more missing.
Rader said a Stone County sheriff's deputy was on the boat when it capsized and was helping to rescue people.
The owner of the tour company involved in the fatal duck boat accident said the vessel should've never been in the water because of the rough conditions brought on by a violent storm.
Mass casualty incidents typically denote at least 10 people killed or injured and as many as 20, Nielsen said.