(CNN) -- A man sought by authorities in connection with a shooting near Auburn University that left three people dead and injured three others, one critically, has previous arrests for gun offenses, but was never prosecuted, according to media reports Monday.

Desmonte Leonard, 22, of Montgomery, is the subject of a multiagency manhunt that stretched into its second day Monday. Leonard faces three charges of capital murder in the shooting late Saturday at an off-campus Auburn, Alabama, apartment complex, police said.

Two former Auburn University football players were among those killed, and a current football player was wounded.

Officers received a call reporting the shooting at the University Heights apartments clubhouse about 10:03 p.m. Saturday, Auburn Police Chief Tommy Dawson told reporters Sunday.

Arriving officers found Edward Christian, 20, dead at the scene. Christian, of Valdosta, Georgia, was off the football team because of an injury, Dawson said.

Former player Ladarious Phillips, 20, and Auburn resident Demario Pitts, 20, died later at a hospital, he said. Two others, including current Auburn sophomore offensive lineman Eric Mack, 20, of Cameron, South Carolina, were taken to East Alabama Medical Center in the nearby town of Opelika.

Mack was released from the medical center about 11 a.m. Sunday after being treated for a gunshot wound, hospital spokesman John Atkinson said. Another man, 19-year-old Xavier Moss, was also treated and released at the Opelika hospital.

A third man, 20-year-old John Robertson, was transferred to the University of Alabama at Birmingham Hospital, where he was in critical condition and undergoing surgery Sunday, police said. Dawson said he had been shot in the head.

Leonard and two other men were thought to have fled the scene in a white Chevrolet Caprice, authorities said. Police later found the car abandoned in an adjacent county, Dawson said, and it was being processed Sunday.

The men believed to have fled with Leonard were being sought for questioning Sunday, Dawson said, but did not release their identities, saying only that "it would probably be in their best interest to come forward."

The Opelika-Auburn News reported Monday that a $15,000 reward -- $10,000 from the FBI and $5,000 from the U.S. Marshals -- was offered for information leading to Leonard's arrest and conviction.

Court records show Leonard was charged in 2008 with theft and carrying a pistol without a permit, and in 2009 he was charged with second-degree assault for allegedly shooting a 16-year-old in the groin, according to the newspaper.

However, the cases were not prosecuted. The Opelika-Auburn News reported that a grand jury declined to indict Leonard on the charges. The Montgomery Advertiser reported that prosecutors did not pursue charges against Leonard in the shooting after the victim said Leonard was not the one who shot him.

Leonard has also been involved in two child support cases, including one filed Friday, The Birmingham News reported. The latest suit claims he is the father of a girl born in 2011. In January, according to the newspaper, a court ruled Leonard was the father of a 4-year-old girl by another woman. He was ordered to pay $305 in child support, $21 of which was to go toward about $7,300 in back child support he owed, the News said.

Police have a motive in the shooting, but Dawson would not release it, saying "that's for the courtroom, later on." He did say authorities believe gunfire erupted during a fight at a party.

Several media outlets cited unidentified witnesses as saying the altercation was over a woman.

Witness Turquorius Vines told affiliate WGCL the violence was sudden.

"It went from us chilling with all these females to a massacre for no reason at all," he said.

"I heard what appeared to be six or seven gunshots outside my apartment," resident Nate Conoly told affiliate ABC 33/40. He said he couldn't see anything when he peered outside his window, but heard screaming. "... I went back into my apartment and locked the door," he said.

Dawson told reporters Sunday that Leonard was thought to be in Montgomery, about 55 miles west of Auburn.

A woman identifying herself as only Leonard's grandmother answered the telephone Sunday at an address listed as his in court records, the Montgomery Advertiser reported.

"I'm just very surprised by all of this," she told the newspaper. "This is not the grandson I know, I can tell you that. I've just been sitting here, can't hardly move, I'm so in shock by it. It just doesn't seem real."

Dawson said he was not aware of any connection between Leonard and the university.

Auburn officials expressed condolences to the victims' families, saying many athletes on the football team were grieving after the deaths of Christian and Phillips.

Former Auburn quarterback Barrett Trotter told ABC 33/40 he was "pretty devastated, pretty shocked just like everyone else at what happened."

"When you have that team, family atmosphere we have at Auburn, anything like that is going to be a real blow to everyone there," he said.

Gene Chizik, Auburn's head football coach, called it "a sad, sad day for everyone associated with the entire Auburn family." Chizik said he was "devastated" by the three deaths, including those of Christian and Phillips, whom he knew personally.

"We have a lot of people on our football team that are hurting right now, and we're going to do everything we can to help them get through this," he said. "We are relieved that Eric Mack, who was also a victim in this incident, is expected to make a full recovery. This is a very trying time for everyone involved, and I would just ask that you lift up the victims and their families in your prayers."

"You don't really know what to do after something like this happens," Trotter told ABC 33/40, "but you have to trust the Lord and believe everything is going to be all right."

CNN's Greg Morrison and Ashley Hayes contributed to this report.