Police are trying to determine what happened at an after-hours club Wednesday morning that led to a man arriving at the hospital with critical injuries.

Dayton Lt. Wendy Stiver said the 23-year-old victim, Demonta Harris, showed up at Miami Valley Hospital with facial injuries at about 4:30 a.m. He sat in the waiting room for some time before anyone realized how badly he was hurt, she said. “The severity of his injuries was not readily apparent.”

According to a police report he sustained “major head trauma” and was taken into surgery. On Thursday afternoon he was listed in critical condition.

Homicide detectives are investigating but have not been able to interview the victim thoroughly.

All that has been determined is that he was involved in some sort of altercation at an after-hours social club called DJ’s, 4919 Hoover Ave. The club does not serve alcohol and usually gets busy about 2 a.m. as bars are closing, Stiver said.