Two offshore powerboat racers died Wednesday after their catamaran went airborne at high speed and crashed, marring the opening of three days of racing at the Key West World Championship, officials said.

Big Thunder Marine — a 46-foot(14-meter) Skater catamaran with four 1,200 horsepower engines that competed in the Superboat Unlimited Class — came down so hard that its right front hull was severely damaged on the third lap of Wednesday's race inside Key West Harbor, organizers said.

Superboat International President John Carbonell said he witnessed the crash, which occurred adjacent to a spectator area.

"He was probably going about 130 mph and the boat's propellers were barely in the water," Carbonell said. "The boat apparently caught some air and went bow (front) up; straight into the air, came down and went backwards."

He identified the dead as Robert M. Morgan, and Jeffrey Tillman. They were piloting the boat as throttleman and driver respectively.

Carbonell said the force of the boat coming down was powerful and crushing.

Despite the accident and rescue efforts, the race later continued. But Carbonell said he stopped the race before the scheduled seventh lap due to another accident, which stretched medical and safety resources. Scott Roman and Ron Roman escaped injury after their Motley Crew boat overturned.

Carbonell said that the world championship will continue with scheduled races Friday and the finals Sunday.