Police say Steve McNair's 20-year-old girlfriend bought the handgun that was found at the scene of the apartment where both were killed and she purchased it less than two days before the shootings.

Nashville police spokesman Don Aaron said Monday that Sahel Kazemi bought the semiautomatic handgun Thursday evening from a person he didn't name.

An autopsy showed that McNair and Kazemi died early Saturday. He was shot four times and his death has been ruled a homicide.

She was shot once and Aaron said police are still waiting for ballistic and gunpowder residue tests before deciding if she was slain or committed suicide.

Aaron said that as far as he knows McNair was not with Kazemi when she got the gun.