LOS ANGELES (AP) — The mother of a Los Angeles County jail inmate has filed a $25 million lawsuit alleging guards fatally beat her son and then tried to cover up the attack.

The federal civil rights suit filed last week alleges that Los Angeles County Sheriff’s Department deputies at the Men’s Central Jail beat Earl Lee Johnson unconscious in September, then hung him from a bedsheet in his cell.

The 24-year-old died three weeks later.

James Orland, an attorney for Johnson’s mother, said Wednesday that the coroner’s office concluded Johnson killed himself by hanging.

But he says the family commissioned its own autopsy, which concluded Johnson died from a fractured skull caused by blunt-force trauma.

Sheriff’s spokeswoman Nicole Nishida says the department hasn’t seen the lawsuit and can’t comment.

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