This could be an american movie. I watched it in Venezuela. There was a group of human-like aliens. I think they were four (4) aliens that acted as the Madagascar penguins, with one as the leader. They were watching a football game and they didn't understand much. Hearing the people yell something like "Referee, why don't you die?", one of the alien kept watching the referee, concentrated and... the referee disappeared in a explosion, leaving out only his clothes. That's the only thing they disintegrate in this movie. They wore dark shirts and shorts as if themselves were football players. They were friendly (though I guess the referee wouldn't agree)
I saw this movie in black and white in the early 70's so it could be anytime before.