RedactedNarrative: On 6/5/21 at approximately 4:03 PM, CPO and I were dispatched to Two Rivers Marina for a reported boat fire and explosion near the fuel pumps.  When we arrived, the vessel (1985 26'' Cruiser Vee Express Cabin Cruiser) was completely burned to the waterline with a small portion of the bow tied to the walk ramp. I spoke with operator who stated she ran the blower while fueling.  Once she had finished, she started the boat and turned off the blower.  The boat died.  She stated she did not turn the blower back on.  She attempted to restart the vessel and once it started she placed it in reverse.  At this time, the initial explosion took place.  
  
  The explosion ejected Subject1 from the vessel and into the water.  During the explosion, Subject1 was struck by an object and was unconscious in the water.  The remaining occupants jumped into the water and bystanders threw life rings and flotation devices to the subjects in the water.  A secondary explosion took place and the vessel became completely engulfed and burned to the waterline.  Subject1 was taken to Pike County Memorial Hospital in Louisiana, MO with a head injury and burns.  Two others rode to the hospital with their mother.  She was conscious at that time.  One person was life flighted to Mercy Hospital in St Louis with second degree burns.  the operator had minor burns on her calves but was treated and released on scene.  
  
  CPO obtained the witness statement below from the fuel attendant who fueled the vessel:
  
  Attendant informed CPO she filled up the vessel with approx. 22 gallons of fuel at $3.99/gal. She stated the operator of the vessel would start the vessel and attempt to place it in reverse.  The vessel would then shut off. Attendant stated the female operator on the second or third try, successfully started the vessel, which at this point was nearing the concrete retaining wall. 
  
  She then placed it in reverse in order to leave the fueling area. Attendant stated the moment it was placed in reverse, the back of the vessel exploded and caught fire. Attendant informed CPO there was a female sitting on what she described as the “sun deck” when the boat exploded. This caused that individual to be ejected into the water. Attendant informed CPO there were no alcoholic beverages in view during the time of the incident and that the operator of the vessel did not appear to be intoxicated in anyway. Attendant informed CPO there were no odd operational behaviors from the operator being displayed at the time of the incident. Attendant stated once the vessel had caught fire, many individuals were helping pull passengers out of the water. 
  
  Further investigation revealed the vessel had not been registered to the current owners and had expired in 2018.  A citation was issued for the violation.  The cause of the accident is undetermined, but suspected to be caused by a failure to remove the fumes from the engine compartment after fueling up.
  