Wow, yes this must be the one! I'm surprised it's from 1977, because I thought it was a late 60's kind of movie. Thanks for the help! I have to see it again...... I think
Andrew, thanks for the link! This was the part I was talking about eariler today:
"On the surface of the planet, everyone starts killing each other. (Or rather, a crudely filmed electrical arc is superimposed between the saucer and Earth. And on in a parking lot, a we are shown a single, isolated incident of a man going on a shooting spree with a .45 automatic, and then he turns it on himself. There. About four down, only a few billion to go. They should have the whole human race exterminated real soon - roughly by the time our sun goes red giant.)"
Thanks for finding this "gem" of a movie!