KNOXVILLE, Tenn. (WATE) — Four people were injured after a boat fire and explosion at Concord Marina Boat Ramp Knox County Saturday evening, according to Tennessee Wildlife Resources Agency.

On Sunday, a spokesperson with TWRA said the fire happened around 6:44 p.m., when a boat had just finished fueling at the marina gas dock exploded and caught fire, injuring the four occupants. While all four had burn injuries, the spokesperson said three were more seriously injured and were taken to a hospital before eventually being life flighted to Vanderbilt Burn Center.

The boat eventually burned to the waterline and sank, the spokesperson added. TWRA and the Knox County Sheriff’s Office Fire Investigation Unit are investigating the incident.

In an update shared Saturday night, Rural Metro said firefighters responded to the reported explosion around 7:35 p.m., where they found a boat fully engulfed in flames and three people with serious burn injuries. The injured individuals were taken to a trauma center, the fire department said.

Rural Metro added that the burning boat was pushed away from the dock and marina, which were only minorly damaged from where burning fuel got underneath.

The fire department urges everyone enjoying the lake this summer to use caution as emergencies can happen when they are least expected.

The Rural Metro initially posted on Twitter around 8:15 p.m., saying firefighters were on the scene of a boat fire and explosion at Concord Boat Ramp.

Three people were taken to a trauma center with “varying degrees of burns,” Rural Metro said.

Boaters are asked to use another boat ramp for the rest of the evening, Rural Metro says.

EDITOR’S NOTE: This story has been updated.