An NBC News producer spoke to the Discovery standoff suspect during the incident.
Police have shot and killed a gunman who was holding three hostages in the lobby of the Discovery Communications Building in Silver Spring, Md. The hostages got out of the building safely. Law enforcement officials confirmed that the suspect is dead.
Montgomery County Police Chief Thomas Manger said officers shot the gunman at about 4:50 p.m. because law enforcement "believed the hostages were in danger" after hours of negotiations.
"We had been talking to him for several hours and he had a wide range of emotions," Manger said.
"Our tactical officers were able to get into position where they were very close to him," Manger said. "They were watching him via camera, and they were close enough to hear what he was saying and see what he was doing on a camera."
At that point, the suspect pulled out a handgun and pointed it at a hostage. Police then shot the suspect, Manger said. It is unconfirmed whether the suspect had fired any shots.
Manger said one of the devices on the gunman's body appeared to go off when he was shot, but that hasn't been confirmed. Manger said people "saw some smoke" and "heard a pop."
"Everyone is accounted for," said Discovery Communications Executive Vice President of Corporate Affairs David Leavy. "Everyone is safe and sound, and we're very thankful for that."
Leavy said police and security handled themselves with complete professionalism. He said the building's emergency evacuation plan was executed flawlessly. Evacuated employees said they were directed to an exit on the Georgia Avenue side of the building.
The building remains a crime scene as police look for other possible explosives. Police believe the suspect brought two boxes and two backpacks -- possibly carrying explosives -- with him into the building. Late Wednesday, Discovery was still waiting for the all clear from police.
Upon learning of the situation, NBC News producers called a general Discovery phone number and were connected to a man identifying himself as the suspect. A producer spoke with the man for about 10 minutes until he apparently ended the call. Meanwhile, other NBC News staff informed authorities.
"I have a gun and I have a bomb," the man told the producer. "I have several bombs strapped to my body ready to go off. I have a device that if I drop it, if i drop it, I'll ******* explode."
He also told the producer he spent three weeks or a month researching and experimenting to prepare the bombs.
"NBC News immediately informed Montgomery County authorities of details of that conversation, but withheld public release of those details while the incident was ongoing," NBC News said in a statement released after the standoff.
Police said an "Asian male" entered One Discovery Place at about 1 p.m. and had "some sort of explosive device on him." Manger said the gunman was wearing "metallic canister devices" that may resemble pipe bombs.
"We are assuming that they could be explosive devices," Manger said during the standoff. "That is the only way we can proceed."
Several people ran from the lobby, but the suspect took three hostages -- a security guard and two other men, one identified as Discovery employee Jim McNulty.
Police said the man made demands and that negotiators spoke with him for several hours.
"His concerns are with the Discovery Corporation right now," Montgomery County Police spokesman Paul Starks said.
NBC News correspondent Pete Williams said a law enforcement official confirmed the name of the suspect: James Jay Lee. He had a history of protest against the Discovery Channel, Williams reported. In March 2008, the 43-year-old man was convicted of disorderly conduct, given six months of supervised probation, and fined $500. For more on Lee, click here.
All employees at One Discovery Place were alerted and either found shelter or were evacuated from the building. Police said the building normally houses about 1,900 employees.
"They told us to lock ourselves in our offices, there was a gunman in the lobby," one witness said. "Later they told us to evacuate down a set of stairs."
Another worker said there was a sense of panic at the building. The worker said they first learned about the incident from a co-worker who had just left to go to lunch and called back.
"A gunman pointed a gun at him and told him to be still, but he kept on going," the employee said about her conversation with her co-worker.
One employee who was on the fifth floor of the building said a message came over the PA system saying there was a situation in the lobby, so employees went to offices to find safety. An e-mail then was sent, saying the might be a gunman in the building.
The employee said they were then evacuated to a wing of the building, and then exited through a parking garage.
"No one was really sure what was going on," the employee said. "Everyone was hearing rumors. It was confusing. A little scary."
Police shut down several roads, including Georgia Avenue and Colesville Road, which are near the building at One Discovery Place. Georgia Avenue was closed between Colesville and Wayne. Authorities said the intersection of Georgia and Colesville could remain closed into the Thursday morning commute. Metro said buses were being re-routed around the area. Metrorail service was not affected, but the entrance from Wayne Avenue was closed.
A daycare center located on the first floor of the building was evacuated. Some children reportedly were wheeled out in cribs. All of the children have been reunited with their parents, police said.
A witness named Rhonda said that at about 1:15 p.m. she was across the street from the Discovery Building and saw about two dozen people running from the building. She said police then secured the outside area.
"When you see people running like that, you know there is a problem," she said.
Twitter user @wasroykosuge tweeted out the following early on: "A bunch of cops w guns and machine guns drawn surrounding the #discovery corporate building."
More unconfirmed info can be found via Twitter at #discovery.
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