I watch this film in 1981. I remember a scene , were a deputy sheriff watch a Group of monks burn a latin girl alive.
He fughts some os the monks , but his car explodes. In the end of the film , the sheriff and onde deputy kill ALL the monks. It’s a American film
“Enter the Devil”(1972)?
Enter the Devil
http://imdb.com/rg/an_share/title/title/tt0068540/
This IS an American film, but there is an Italian film from 1974, called L ‘Ossessa, but also called ‘Enter the Devil’ in the U.S. The one you’re looking for is available from Sinistercinema.com.
Oh, despite the title Enter the Devil, the film never mentions Satan or devil worship. It was also re-released as. “Disciples of Death”.