Dave Martin / AP
Law enforcement officials use a body sensing device to search a home in Montgomery, Ala., Monday, June 11, 2012. Authorities searching for the man charged with fatally shooting three people near Auburn University swarmed the house Monday where they believe he's hiding, firing tear gas and sending a tactical team on cautious forays inside.
Updated at 5:30 a.m. ET: Authorities in Montgomery left a home early Tuesday where they believed the man charged with fatally shooting three people near Auburn University might have been hiding.
Law enforcement swarmed the scene Monday afternoon and spent hours firing tear gas, using thermal imaging and sending tactical teams on forays inside the house as they searched for Desmonte Leonard. They hadn't brought anyone out of the home by the time they held a briefing just after midnight.
And around 2:25 a.m. (3:25 a.m. ET) Tuesday, an Associated Press photographer on the scene saw all law enforcement agents that had been there leave without comment. It wasn't immediately clear why they left. There was no activity around the house.
Leonard is charged with three counts of capital murder in a shooting Saturday night during a pool party at University Heights apartments. He's also accused of wounding three others. The dead included two former Auburn football players.
Earlier the tactical team searched the lower portions of the house and made deliberate moves into the attic where Leonard was believed to be hiding, Montgomery Public Safety Director Chris Murphy told the AP. The attic is cramped, complicating investigators' efforts.
Montgomery Police Sgt. Regina Duckett said coughing and movement was heard inside.
"We are having to slowly put our people up there and do an inch-by-inch search," Murphy said during a briefing several hours after police surrounded the house.
Police had hoped to flush out the person with tear gas and verbal commands, but sent in the tactical team after getting no response.
"This is a pretty driven person. He's got nothing to lose," Murphy said. "You cannot rush it."
Murphy said investigators believe he's likely covered in insulation and suffering effects from the tear gas.
Dave Martin / AP
Police officers with automatic weapons stand outside a home in Montgomery, Ala. on Monday. They believe the man suspected in the Auburn shootings entered the home.
"He's got to be in a lot of pain," he said.
On Monday, police received two 911 calls that Leonard had entered the house but did not have "unequivocal confirmation," said Montgomery Mayor Todd Strange.
"Whoever is in there doesn't want to come out," Strange said.
'Massacre for no reason'
Police have arrested two men in connection with the shooting: Jeremy Thomas, 18, is being questioned for hindering prosecution, the Atlanta Journal-Constitution reported, and Gabriel Thomas, 41, was arrested late Sunday for allegedly providing false information to police.
Auburn Police Chief Tommy Dawson said nine police agencies are involved in the search for Leonard.
The shooting occurred before midnight on Saturday at the University Heights apartments, a large complex near campus favored by Auburn University's students and athletes.
Leonard is suspected of pulling a gun after a fight broke out, shooting six, Dawson said at a news conference on Sunday. He apparently fled in a white Chevrolet Caprice, which he later ditched.
Todd J. Van Emst / Auburn University via AP file
Edward Christian, 20, left, an Auburn University student and former football player, was fatally shot at a pool party about two miles from the university on Saturday night. Eric Mack, 20, center, was treated and released; Ladarious Phillips, 20, a student and former offensive fullback for the football team, was also killed.
Montgomery police had previously arrested Leonard in 2008 for carrying a gun without a license, according to court documents obtained by The Associated Press.
When police arrived at the scene, Edward Christian, 20, was found dead on the sidewalk. Christian was a student and former offensive lineman for the Auburn Tigers football team.
Ladarious Phillips and DeMario Pitts, both 20, were transported to the hospital, where they later died. Phillips was a student and former backup fullback who gave up football in April, according to his coach. Pitts lived in Auburn.
Three young men, including two students, were killed and three others wounded in a Saturday night shooting in Auburn, Ala. A manhunt was underway for the suspect. NBC's Mark Potter reports.
Turquorius Vines, who was at the party, told the Journal-Constitution the fight erupted because of a girl.
The night, he said, "went from us chilling with all these females to a massacre for no reason at all. It happened so quick, in about a second."
For Vines, the shooting has left him reeling.
"It's like I lost a lung," he said. "I don't know how I'm going to survive this."
Among the wounded, John Robertson, 20, remained in critical condition on Monday after being shot in the head. Xavier Moss, 19, was released from the hospital after the shooting. Eric Mack, 20, an offensive lineman who was shot in the buttocks, was released late Sunday afternoon.
Mack is a junior offensive lineman from St. Matthews, S.C. He played in five games last season. Coach Gene Chizik said on Sunday that Mack was expected to make a full recovery.
Police Chief Tommy Dawson said he believed the shooting was "a fight that obviously got out of hand."
The shooting has shaken Auburn, a city of 53,000 that revolves around the football team. The Auburn Tigers have won two national championships, most recently in 2011 against the University of Oregon. Cam Newton, a quarterback, won the coveted Heisman Trophy that year.
The Associated Press and msnbc.com's Isolde Raftery, Mark Stevenson and Marian Smith contributed to this report.
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