There were more than 20 people on the boat when it capsized, Nielsen said.
Earlier, he said more than 10 people were injured.
“We did have a severe thunderstorm, not sure if that is the contributing factor,” he said. “There is a lot of storm debris.”
A spokeswoman for Ripley Entertainment, the parent company of Ride the Ducks Branson, said the company is in contact with their employees at the scene, said.
Suzanne Smagala-Potts said the company recently acquired the vessel that was involved in the incident.
There were other boats on the lake that returned to dock safely.
Divers representing various agencies are on scene to assist with the investigation and recovery.
At least six patients were treated at CoxHealth Medical Center, hospital spokeswoman Kaitlyn McConnell said.
McConnell didn’t comment on the nature of the victims’ injuries.
Developing story — more to come
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