Desert of Fire (1971)

Original title: Deserto di fuoco

A desert bandit leader robs a jeep and hauls off a lot of American money. He doesn't get much of a chance to enjoy it, however, because he and his men are soon attacked by a "phantom", who kills all his men, and steals his weapons. When a beautiful young woman shows up in search of the money, she is raped by the phantom. When another man shows up the three of them decide to head into the desert to find the "treasure" and wind up finding something they weren't expecting.