NASHVILLE, Tenn. - Shot twice in the head and two more times in the chest, former NFL quarterback Steve McNair was the victim of a homicide, police declared Sunday. But authorities wouldn’t say it was a murder-suicide — even with his 20-year-old girlfriend dead at his feet from a single bullet.

McNair had been dating Saleh Kazemi for several months, and Nashville police spokesman Don Aaron said Sunday that a semiautomatic pistol was found under her body. She was shot in the head.

McNair, who was married with four sons, had a permit to carry a handgun in Tennessee, and he was arrested once before with a 9mm weapon although charges in the case were dropped. Police said they had not yet determined who owned the gun found at the scene.

Investigators weren’t looking for a suspect but were questioning friends of the couple as well as Kazemi’s ex-boyfriend. They were also waiting for results of drug and other laboratory tests before deciding whether McNair was killed in a lovers’ quarrel.

“That’s a very important part of the investigation as we work to ultimately classify Miss Kazemi’s death,” Aaron said.

The details surfacing after McNair’s death stand in stark contrast to the public persona he enjoyed during his career.

McNair repeatedly played through serious injuries and pain to win, though he came up a yard short of forcing overtime on the Tennessee Titans’ famous drive to lose the 2000 Super Bowl.

Generous, he frequently took part in charity work for both the Titans and later the Baltimore Ravens after a 2006 trade. McNair even helped load donated food, water and clothes onto tractor-trailers that he had arranged for Hurricane Katrina victims, and paid for three football camps for children himself this year.

McNair and Kazemi were found dead at a Nashville condominium — which overlooks the Titans stadium — that he rented with his friend Wayne Neeley. Police believe both died early Saturday. Neeley found the bodies hours later, and called a friend, Robert Gaddy, who played at Alcorn State with McNair. Gaddy dialed 911.

“People have certain things that they do in life,” Gaddy said. “We don’t need to look on the situation at this time (but) on the fact we just lost a great member of society.”

The quarterback’s agent, Bus Cook, said he had never heard Kazemi’s name until news of the shooting broke Saturday. What McNair’s wife knew wasn’t clear Sunday. Cook said Mechelle McNair was “in and out of it.” He said she had no comment after the police called his death a homicide.

“It doesn’t make any sense. I don’t know what to say,” Cook said.

Mechelle was “very upset, very distraught” Sunday, Cook said. She was preparing to finish funeral arrangements Monday.

Video   Victim’s sister discusses McNair relationship July 5: The sister of Sahel Kazemi talks about Sahel's relationship with former NFL player Steve McNair. Sahel Kazemi and McNair were found dead Saturday. MSNBC

McNair split his time between Nashville and his farm in Mount Olive, Miss. He recently opened a restaurant near Tennessee State University that was aimed at serving healthy, affordable food to college students.

McNair was also seen so often at Kazemi’s apartment that a neighbor thought he lived there.

McNair met Kazemi when his family ate often at the Dave & Buster’s restaurant she worked at as a server, and the two began dating in a relationship that included a vacation with parasailing. Photos posted on TMZ.com showed McNair gazing and smiling at the young Kazemi.

“She pretty obviously got mixed up way over her head with folks,” said Reagan Howard, a neighbor of Kazemi’s.

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A man who answered the door at a house in the Jacksonville, Fla., suburb of Orange Park said it was the home of Kazemi’s family, but said her relatives did not want to comment.

“We don’t have anything to say, please leave us alone,” he said.

Kazemi's niece said the 20-year-old was not capable of killing, the Tennessean reported.

"She would never kill anyone, ever," said Sepidah Salmani, the Tennessean reported. "Or anything. Not even a little bug. I want people to know that."

The victim’s sister, Soheyla Kazemi, told the Florida Times-Union in Jacksonville that the young woman had expected McNair to get a divorce. “She said they were planning to get married.”

An ex-boyfriend told the Tennessean he was worried about Kazemi dating McNair because he was married.

“She is the sweetest girl, and she did not deserve this,” said Keith Norfleet, her ex-boyfriend, according to the newspaper. “He (McNair) was making her believe they were going to be together and everything would be perfect.”

Norfleet said he thought Kazemi was planning to break up with McNair, the Tennessean reported.

Kazemi often was dropped off by limousine in the early morning hours and recently went from driving a Kia to a 2007 Cadillac Escalade registered to both herself and McNair. Her niece told The Tennessean that Kazemi thought McNair was divorcing his wife of 12 years soon.

Nashville courts had no record of a McNair divorce case, but a home he owned in Nashville is on the market for $3 million.

The real estate agent declined to comment. Her online listing for property described it as a “gigantic house” of more than 14,000 square feet and photos showed a pool, home theater, baby grand piano and ornate furnishings throughout.

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