UPDATE: Spilled fuel caused the explosion in the back of the delivery truck Wednesday afternoon that injured two people, according to the Lynchburg Fire Marshal's Office.

The generator in the the back of the truck had recently been used and tipped over spilling fuel onto insulation that was being delivered.

The two men who were traveling in the truck are recovering from severe burns following the explosion.

The two had pulled into the parking lot of the Lakeside Drive Quik-E Food Store to reportedly investigate smoke in the vehicle when the first explosion occurred. Employees immediately cut the gasoline pumps off and called 911.

photos/ABC 13

Eyewitnesses reported two explosions and believed the two people in the truck had exited and opened the back doors around the time of the first explosion. A second explosion came minutes later, they said. 

The two men were transported to the hospital where they are being treated for severe burns. One witness described one of the men rolling on the ground after catching fire. 

UPDATE: A spokesperson for the insulation company said one of the men was flown to the University of Virginia Medical Center yesterday and the other person was expected to be released from the hospital today.

The truck was transporting insulation products, said to be highly flammable, according to ABC 13. Officials noted that a generator was on the truck. 

We certainly hope the two people will be okay.