I was watching this on UK television one afternoon in the 1980's. Subtitles and I think they were speaking Spanish (or Italian/French maybe - poor ear for languages) but my first wife came home and insisted on watching some soap so I never saw the end of the film.
A priest finished his service in a small town church but none of the congregation would leave the building, he strode down the aisle but stopped before he got to the doors, he couldn't leave either.
As the day progresses various villagers enter the church to see where their family members have got to, they too can't bring themselves to leave. Eventually the local police get involved and send in a cop, he doesn't come out either.
The view kept switching from the gathering crowds behind hastily erected barriers and the trapped people inside. I think a very well trained dog was sent in but wouldn't come out despite the owner calling through the door...(the church inner porch doors weren't in line with the main doors so nobody could see in or out)
The police chief called in the army but in the meantime somehow got hold of a flock of sheep and drove them in to see what happened, they milled around the trapped people but, despite a lot of arm waving and shouting and trying to herd them with the dog, they too would not venture back to the church doors.
That's as far as I viewed it, unfortunately