Blood Calls to Blood (1968)

In a frontier town between the USA and Mexico, Sancho and his gang assault a monastery, kill a few monks who try to oppose the invasion of the sacred building, and get away with a work of art in gold and diamonds. Andrej, a lonesome cowboy, is informed of his brother's death, one of the monks, and starts a search for the gang. Among the lawless and godless men, a fight for getting the better part of the loot is taking place and blood is flowing as much as bullets.