Kentucky Fish and Wildlife Conservation Officer Daniel Richardson tells news outlets a couple were on board the 32-foot (10-meter) cruiser at Green Turtle Bay Marina when the blast occurred Sunday. He says the explosion came after the motor was started while the boat was tied to the fuel island.
He says nothing currently indicates that the explosion was caused by anything but mechanical failure.
The husband and wife were treated at hospital with what Livingston County emergency management official David Koon said were "moderate" injuries. Koon says six others were treated at the scene.
Richardson says the boat was completely destroyed, with "debris for 100 yards."