MONTGOMERY, Alabama (CNN) -- Authorities have surrounded a house in Montgomery, where they believe the man accused of killing three people and wounding three others near Auburn University last weekend was holed up Monday evening.
Police had already used "a powerful dose" of tear gas in an attempt to force out the suspect, Montgomery Mayor Todd Strange told reporters. But that effort failed, and investigators are prepared for a long night, he said.
"Time is on our side," Strange said, adding, "It'd be very difficult for us to go in, but if we have to, we will."
Strange said he "cannot unequivocally" say the person in the attic was 22-year-old Desmonte Leonard, now wanted on three counts of capital murder. But he said the call that brought police to the scene "indicated that a person that looked like the suspect might be in this house."
Another caller "a bit earlier" had reported someone who resembled Leonard was in the area, Strange said. And Montgomery County Sheriff D.T. Marshall said the owner of the house returned home to find the suspect inside and called police.
Saturday night's shootings took place at an off-campus apartment complex in Auburn, about 50 miles east of Montgomery. The dead included two former Auburn football players, and a current football player was among the wounded.
Leonard has been the target of an intense manhunt for two days, and two other men have been jailed on charges of hindering prosecution in the case.
Auburn police said one of those arrested, 18-year-old Jeremy Thomas, escaped from the scene of the shootings with Leonard. Montgomery police say 41-year-old Gabriel Thomas tried to mislead investigators during the search, and they arrested him Sunday at the request of U.S. marshals.
Police did not immediately disclose the relationship, if any, between the two men. Both were arrested in Montgomery, but Jeremy Thomas was expected to be transferred to a jail in Lee County, which includes Auburn, police said.
Leonard, a Montgomery resident, had previous arrests for gun offenses, but was never prosecuted, according to media reports. He was still believed to be in the state on Monday, Montgomery Police Chief Kevin Murphy said.
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 Sunday morning, while another man, 19-year-old Xavier Moss, was treated and released from the same facility.
A third man, 20-year-old John Robertson, was transferred to the University of Alabama at Birmingham Hospital, where he was in critical condition after being 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.
The Opelika-Auburn News reported Monday that a $15,000 reward -- $10,000 from the FBI and $5,000 from the U.S. Marshals Service -- was offered for information leading to Leonard's arrest and conviction.
Court records show that 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 also has 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.