At least 17 people have died , including nine members of one family, after a tourist boat capsized Thursday in Table Rock Lake near Branson, Missouri, according to emergency officials.

Stone County Sheriff Doug Rader said Friday in a news conference that the Missouri Highway Patrol Dive Team had returned to the water that morning to recover the bodies of four more people, increasing the death toll. Fourteen survivors have been accounted for, including seven who were hospitalized. Two have critical injuries.

The Southern Stone County Fire Protection District said multiple agencies responded to a mass casualty call shortly after 7 p.m. local time for an amphibious duck boat that was carrying 31 people, including children. The vehicle is owned by Ride the Ducks, a popular tourist company with offices in several cities. The craft, which can be piloted in both water and on land, capsized as severe thunderstorms were moving through the area and has since sunk , according to KSDK-TV in St. Louis.

I believe it was caused by the weather, Rader originally said during a Thursday news briefing, adding that the Coast Guard and National Transportation Safety Board are leading the investigation. Later on Friday, Rader said it was too early in the investigation to determine the cause.

A video taken from a restaurant on the lake shows a Ride the Ducks boat, which appears to have enclosed sides, attempting to navigate through rough waves. Investigators told local news outlet KY3 that two of the companys boats were on the lake at the time, and one made it back safely . Its unclear if the vehicle in the video was the one that sank.

The captain of the boat survived, but the driver did not, Rader said Friday. The police are still notifying families and are not providing any other information about the rest of the victims.

Missouri Gov. Michael Parson (R) told CNN he met with one survivor who lost nine members of her family in the accident.

Its difficult to find the right words to say, he said of the meeting.

The divers located the boat and will probably recover it later Friday, Rader added. Life jackets were also reportedly on the boat, but Rader said he could not answer if anyone was wearing one.