Authorities in Montgomery, Ala., on Tuesday defended their hunt for Desmonte Leonard, the man charged with fatally shooting three people at a party near Auburn University, NBC station WSFA in Auburn reported.

"We have not rested, we will not rest," Auburn Police Chief Tommy Dawson said at a news conference Tuesday. "If he's out there watching today, I implore him, this has gone on long enough."

On Monday and early Tuesday, police searched a house in Montgomery, using thermal imaging to see if anyone was in the attic. Police said they thought they heard someone coughing, but nothing was found, WSFA reported.

Dawson said authorities received a tip from someone who said they dropped Leonard off at the home, and then received a 911 call indicating that he was inside. He said the tips were independent from each other. 

Montgomery Police Chief Kevin Murphy told reporters that "whoever dropped him off knew they were a suspect and were aiding him." That person could possibly face charges Murphy said, WSFA reported. 

Dawson said that an earlier Reuters report that authorities searched the wrong house is false.

At the press conference, Dawson said police are still at the home. He reiterated that he believes the suspect is still in Montgomery, WSFA reported.  

He said that he spoke with Leonard's mother and that she told him if he contacted her she would alert the police. Dawson said that she is urging her son to turn himself in, WSFA reported.

Authorities noted that Leonard's face and name have been all over the news media since Saturday. 

 "Doesn't matter where he's at," Dawson told reporters. "We've got the FBI on this case and U.S. marshals." 

A reward for his capture is up to $30,000, thanks to commitments from Auburn University and the city of Montgomery, WSFA reported. 

"We're going to apprehend him sooner or later," Dawson said. "I implore him to turn himself in."

Leonard is charged with three counts of murder in a shooting during a pool party at the University Heights apartments Saturday in Auburn. He's accused of pulling out a gun after a fight broke out. Two of those killed were former Auburn football players. In addition, he's accused of wounding three others, one of whom is in critical condition with a head wound. The others have been released from the hospital. 

Dawson said he believes the fight was about a girl. 

Two men have been arrested in connection with the shooting. Gabriel Thomas, 41, was arrested Sunday and accused of giving false information to police, and Jeremy Thomas, 18, is accused of hindering prosecution, the Atlanta Journal-Constitution reported. 

Two of those killed, Edward Christian, 20, and Ladarious Phillips, 20, were students and former football players for the  Auburn Tigers. Christian played offensive lineman and Phillips was a backup fullback who gave up football in April, according to a coach. 

Also killed was DeMario Pitts, 20. 

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