The inmate said he was summoned to a spot under a stairway where no jail guards or cameras would be able to see.
There, he said, three other Los Angeles County inmates ambushed him, leaving him with a busted jaw and broken nose, a concussion, double vision and blood oozing from his face.
The inmate, Saul Steve Lira, said the guard on duty deliberately ignored what was going on.
Now, prosecutors have charged the guard with assault, accusing him of walking away at the request of another inmate so Lira could be beaten and later refusing to assist Lira with medical help.
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