Tony Hall, 49, of Clarksville, Fla., was driving a semi-truck west of SR 20 near Cedar Beach Cove when he rear-ended a minivan about 11:45 a.m., according to a report from Florida Highway Patrol.
David Waters, 61, of Freeport, was driving the minivan and slowed to make a right turn. Hall did not slow down in time to stop, according to the report. He swerved to the left, but was unable to avoid hitting the back of the minivan.
The fuel tank of the semi-truck was punctured during the crash and was leaking fuel onto the highway, according to FHP Lt. Steven Preston.
Walton County hazardous materials crews worked until 5 p.m. cleaning up the fuel leak, according to Mike Morrison of the Walton County Sheriff's Office. All lanes are open now.
Waters was critically injured and was flown to Bay Medical Center in Panama City, according to the FHP report. Hall sustained minor injuries and was taken to Twin Cities Hospital in Niceville.
Charges are pending, according to FHP.