PHILADELPHIA (CBS) – Philadelphia police are investigating what they believe is the sexual assault of a woman late Sunday night.

The reported assault happened at about 11 p.m. in the city’s Hunting Park neighborhood.

According to investigators, the unidentified 31-year-old female was found near the Greenmount Cemetery at Front Street and Hunting Park Avenue.

Authorities say the victim was taken by ambulance to Temple University Hospital with severe head injuries. Sources say while the victim was being transported to the hospital, she was experiencing loss of consciousness.

Investigators believe the woman was a victim of a sexual and physical assault.

The incident remains under investigation by the Special Victims Unit.