About 12 seconds was all it took for two bailiffs to gun down a man who shot at them in a courthouse lobby, and authorities said the swift response helped prevent anyone else from being seriously hurt.

Glen Lee Powell carried a semiautomatic handgun, 79 rounds of ammunition, an extra gun magazine, a lengthy fighting knife and a gas mask into the downtown St. Petersburg courthouse just after the lunch hour Wednesday. He fired at least two shots before Deputies B.J. Lyons and Marvin Glover fatally wounded him, Pinellas County sheriff's Sgt. Jim Bordner said Thursday.

Four other people were in the lobby at the time of the shooting but the only other person hurt was Lyons, who was hit in the shoulder by a bullet that Bordner said may have been deflected by a piece of his two-way radio. He was treated and released from a hospital.

Bordner said about 12 seconds elapsed from the moment Powell entered the lobby until the gunfight ended.

While detectives scoured the 30-year-old's truck and other belongings in search of a motive, his mother said he was a frequent visitor to anti-government Web sites and harbored a deep distrust of police and other authorities.

"I just think he believed a bunch of lies," Virginia Powell told the St. Petersburg Times. "I can't imagine that he would have actually tried to kill anybody. I think he was trying to make some kind of statement."

She did not return a phone message left Thursday by The Associated Press.

Glen Powell's family and a pastor in his church said he may have been going to the courthouse to meet a deadline for filing paperwork in his divorce, but his mother said she did not think the divorce played a factor in the shooting.

Bordner declined to speculate on Glen Powell's possible motives, saying, "We may never know." He said he was not aware of any writings or court documents being found on Powell or in his backpack.

Authorities said Lyons and Glover remain on routine, paid leave while the shooting is investigated.

Virginia Powell said her son was a high school wrestling champ, served in the Air Force in California and did a stint as a Mormon missionary in Colombia.

She told The Tampa Tribune she asked to go with her son to the courthouse, which is in a neighboring county from their home in the Tampa suburb of Brandon, but he refused.

The courthouse reopened Thursday morning. Procedures were being reviewed, Bordner said, but the building had recently received a security upgrade and the swift reaction by deputies indicated existing policies were adequate.

"I think yesterday's situation, while it's a sad and tragic event, I think it demonstrates the security we have in place works," Bordner said.

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