DAYTONA BEACH, Fla. — Investigators believe a gas leak caused a fireball to ignite, resulting in a 34-foot boat to explode Sunday afternoon at Daytona Beach Marina, injuring four people and sending one to a hospital.

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The boat exploded at the dock around 1:15 p.m. on Sunday.

Investigators said the owner told them he had just finished refueling when one of the passengers tried to start the engine, causing the explosion.

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Boat explosion injuries 4 boaters in Volusia County, firefighters say (Daytona Beach Fire Department)

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A woman in her 50s was airlifted more than an hour away to Orlando Regional Medical Center because of the seriousness of her injuries. Her condition is not known. Three others were treated for their injuries at the marina.

Investigators said the boat’s blower vents were running while they were refueling. Firefighters do not know if any other vapors leaked into the hull.

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VIDEO: Boat explosion injuries 4 boaters in Volusia County, firefighters say VIDEO: Boat explosion injuries 4 boaters in Volusia County, firefighters say (WFTV)

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