RedactedNarrative: OPERATOR 1 WAS ATTEMPTING TO START VESSEL 1 WHILE IT WAS DOCKED IN A DOCK SLIP. AS OPERATOR 1 WAS ATTEMPTING TO GET VESSEL 1 STARTED AN UNKNOWN INDIVIDUAL WAS TRYING TO ASSIST OPERATOR 1 WHEN THEY USED A KNIFE IN THE ENGINE COMPARTMENT OF VESSEL 1. THIS CAUSED THE GAS FUMES THAT HAD ACCUMULATED IN THE ENGINE COMPARTMENT FROM ATTEMPTING TO START VESSEL 1 TO EXPLODE WHEN THE KNIFE WAS USED CAUSING A SPARK. OPERATOR 1 SUSTAINED INJURIES FROM THE FIRE AND VESSEL 1 WAS A TOTAL LOSS.