RedactedNarrative: On august 01, 2020 i, u.s. park ranger, responded to the las vegas boat harbor fuel dock for a report of a vessel fire. I arrived on scene and was informed by a marina employee the fire was extinguished by las vegas boat harbor (lvbg) personnel. Contacted the owner and operator of the boat, operator 1. She reported she had just fueled the boat and was drifting away from the fuel dock.
  
   Operator 1 stated when she started the engine an explosion occurred in the engine compartment and up the center of the vessel. Operator 1 and passengers reported the explosion cause the engine cover to come open and the engine compartment was smoking. Operator 1 and passengers exited the vessel immediately. Lvbh personnel reported suppressing the smoke with a fire extinguisher and then pushed the boat away from the fuel dock towards shore. 
  
  The vessel was an inboard/outboard. Operator 1 reported she did not have her blower on and does not turn it on after fueling. Operator 1 reported they vented the boat after fueling by leaving the gas cap off. All passenger''s reported they were okay and did not require medical attention one passenger advised she had a light burn on her arm, but stated she did not need medical attention. Due to the vessel free floating in the water, i was unable to inspect the damage or for required equipment.  Operator 1 later advised the manufacturer of the vessel inspected the vessel and reported the clamps on the fuel line that connect to the gas tank had failed.