Police chief Nate Harper makes a public plea for people to stop communicating with the suspected gunman in an ongoing hostage situation at a local office building so that his team can finish negotiations and bring the ordeal to an end.

Updated at 2:31 p.m. ET: An armed man who took a hostage inside a Pittsburgh high-rise building has released his hostage and surrendered, authorities said.

Pittsburgh Police Chief Nate Harper identified the suspect as 22-year-old Klein Michael Thaxton. Harper said Thaxton entered the 16th floor office of a benefits administration firm around 8 a.m. and asked for the man he eventually took hostage.

Police had evacuated the downtown Pittsburgh building, Three Gateway Center, and surrounded it with county, state and federal agents.

During the standoff, Harper made a public plea for people to stop communicating with the suspect on social network sites. The suspect had been posting Facebook updates as police tried to negotiate with the suspect. The Facebook page was later removed, NBC News has confirmed.

“No one has been hurt at this time. There have been no shots fired at this time. The individual walked in to the investment office and started asking questions," Harper said.

It is not clear if Thaxton, who police said is in his 20s, was an employee in the building. Police said he was a former member of the military and has a criminal background.

Harper said Thaxton had been calm and cooperative during the negotiations, and had not made any demands.





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Pittsburgh police chief Nate Harper says the man behind an ongoing hostage situation at a local office building has been identified as somebody with a military background.

Thaxton's mother was taken into the building had tried to reach out to him.

The 16th floor had been placed on lockdown, and parts of the building have been evacuated.

Workers were seen walking away from the Gateway Center complex, which is a high-rise building complex with four buildings. Police were urging people to stay away from the scene. Bus routes in the area have been rerouted and the Fort Pitt Bridge is closed.

Thaxton has had run-ins with the law before. Police reportedly took him into custody last year after a lengthy chase that ended with him jumping from the roof of an auto body shop in Pittsburgh.

Gene J. Puskar / AP Police block off the area around Three Gateway Center, building left rear, where they are negotiating with a man who claims to have a bomb, in downtown Pittsburgh on Friday.

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