Relatives of a man who died in a Mississippi jail last May are suing, claiming witnesses saw jail guards beat the man before his death.

The suit was filed Tuesday in federal court in Jackson by Betty Hill, the mother of the late Harvey Hill.

Madison County Coroner Alex Breeland says he doesn’t know why Hill died. Breeland says the state medical examiner has yet to return final autopsy results for the 36-year-old Hill. Mississippi’s crime lab has a months-long backlog because of a shortage of pathologists to complete autopsies.

Lawyers say Harvey Hill was beaten by guards while handcuffed, pepper sprayed and then returned to his cell in need of medical attention.

Madison County sheriff’s spokesman Heath Hall is declining comment, saying lawyers haven’t seen the lawsuit.