An autopsy revealed this afternoon that a man found lying dead Saturday morning in Washington Park was beaten to death.

Shortly after 7 a.m. Saturday, police responded to a call of a man down on the 5100 block of Ellsworth Drive and found a man in his 20s lying in the grass in the park, police said.

Police initially thought the man was shot in the back of the head, but an autopsy this afternoon revealed the man died of craniocerebral injuries due to a beating, according to the Cook County medical examiner's office.

The man, who has not been identified as of 4 p.m. Sunday, was pronounced dead at 7:45 a.m. Saturday at the University of Chicago Hospitals, according to the medical examiner's office.

There were no witnesses to the crime, police said earlier.

As of 4 p.m., police were conducting a homicide investigation into the man's death.

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