NASHVILLE, Tennessee, (AFP) - Former American gridiron star Steve McNair was shot four times in what Tennessee police are now ruling a killing.

The ex-Tennessee Titans and Baltimore Ravens quarterback and a female friend were found shot to death Saturday at a home in downtown Nashville. Police are now saying the female is 20-year-old Sahel Kazemi.

Nashville police spokesman Don Aaron said Sunday they do not have a motive but the investigation is continuing.

McNair had multiple gunshot wounds Aaron said, including two in the head and two in the chest. Aaron added a handgun was found near Kazemi's body.

Police said that McNair, married and a father of four, and Kazemi had been dating.

Officils declined to classify Kazemi's death but have not ruled out a murder-suicide among other possible motives.

A three-time Pro Bowl selection, McNair shared the most valuable player of the NFL award in 2003.

In 161 games (153 starts), McNair threw for 31,304 yards on 2,733- of-4,544 passing, with 174 touchdowns. He also ran for 3,590 career yards and 37 TDs.

McNair last played in the NFL in 2007 for the Ravens. He is a former third overall pick by Houston in the NFL's 1995 entry draft.