An armed man continues to negotiate with police as he holds a hostage onthe 16th floor of Three Gateway Center, Downtown.
No shots have been fired, and no one is hurt in the hours-long standoff, though one to two individuals are being held hostage in the offices of law firm Breitsman Associates, police said.
The suspect is identified as Klein Michael Thaxton, 22, according to KDKA and WPXI. Police initially said he is from Altoona, Blair County, but court records show his address as McKeesport. Authorities have not determined his motivation for the stand-off.
Pittsburgh Police negotiators are speaking to Thaxton, who police said had served in the military They have described him as cooperative. Workers in Gateway Center have left the building, the Post-Gazette reports. FBI agents, Allegheny County police and other agencies also have responded.
Here's how the ongoing event has unfolded:
8:16 a.m. A man walks into the 16th floor of Three Gateway Center and speaks to employees in Suite 1625.
8:32 a.m. Pittsburgh Police SWAT team is called to Three Gateway Center for a report of a man with a gun.The man reportedly will shoot anyone who approaches the building's upper floors. A hostage negotiator is called.
8:45: Pittsburgh Police begin to flood Gateway Center, Golden Triangle area with uniformed and SWAT officers, vehicles and equipment.
8:47 a.m. Police report that a man is barricaded on the 16th floor with one hostage and claiming he has a bomb.
9 a.m. Gateway T station is closed and trains are not picking up/dropping off there. Traffic is routed away from Gateway Center and the Golden Triangle, as is bus service.
9:20 a.m. Three Pittsburgh Police hostage negotiators are on the scene. Pittsburgh Police Chief Nathan Harper holds first press briefing. Watch it here on WPXI.
9:55 a.m. Pittsburgh Police Chief Harper holds press update, says no shots have been fired and no one is hurt in the incident. He says one black man is holding one, possibly two hostages.
About 10 a.m. Hostage update: #WPXI viewer called to say this is happening at the CW Breitsman insurance office, Three Gateway building in Pittsburgh. C.W. Breitsman handles pension plans for the International Association of Theatrical Stage Employees Local 3, the Steamfitters Union and other clients.
10:19 a.m. The only bus stops that are affected now are Liberty Avenue at the Wyndham hotel and Liberty Avenue at Four Gateway Center. Commuters are permitted to use other regular stops.
10:27 a.m. Harper tells KDKA, WPXI and other reporters that other floors have not been evacuated because the hostage situation is contained to the 16th floor. #threegateway
10:40 a.m. Harper says other floors of Three Gateway have not been evacuated because situation contained to the 16th floor.
Just before 11 a.m. Harper said the gunman's mother has been brought to Three Gateway. He says the gun man is in his 20s, was in the military and has a criminal background: http://cbsloc.al/REY2DD
11:10 a.m. WPXI reports the suspect's name is Klein Michael Thaxton, and that he does not work in the building #threegateway. KDKA identified him as Klein Michael Thaxton, 22, from the Altoona area in Blair County.
11:20 a.m.: WTAE reports Thaxton has a criminal history, including previous arrests for making terroristic threats and robbery.
11:50 a.m. Thaxton appears to be posting updates in real time to his Facebook page, expressing outrage. Click here to view the page.
12:15 p.m. Police ask others to stop posting and responding to Thaxton's Facebook posts.
1 p.m. Pittsburgh Public Safety Director Michael Huss issues statement asking media to refrain from reporting on information from Thaxton's Facebook page until the situation has been resolved. "It is in the best interest of public safety to contain the information that is being viewed by the hostage suspect," Huss said. We appreciate the public's patience and encourage the media and public to stay updated through Chief Harper."
1:15 p.m. Police escort woman identified earlier as Thaxton's mother out of Three Gateway Center.
1:15 p.m. Thaxton's Facebook page is taken down and no longer available for public viewing.
1:35 p.m. Harper says police shut down Thaxton's Facebook page because they "want his full attention." The chief also says Thaxton has told negotiators he does not have explosives and does not want to live.
1:50 p.m. Thaxton is in custody. Hostage is reportedly safe.
1:55 p.m. SWAT officers assemble in lobby of building.
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