Movie where they r excavating in a town

Movies
1

B&w movie

— Excavating roundish objects from a spot in town
— At end, town is on fire and people are escaping on bus(?) while devil shadow stands over town laughing

Just a vague lead: https://www.imdb.com/search/title/?title_type=feature,tv_movie,tv_miniseries&genres=!documentary,!short&plot=excavation&colors=black_and_white&sort=release_date,desc

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