Tank Filler Pipe And Cap problems of the 1998 Toyota Avalon

While refueling vehicle at a gas station consumer set the pump on automatic and walked off a few feet, turned around and noticed flames shooting out of filler neck. Flame was put out with a extinguisher, and vehicle towed back to dealer. Fire dept report stated gas station pump ignited fire from spark of unknown souce. No smoking or people around at the time.