Montgomery County, Md. police department sources say the hostage-taker at the Discover Channel building had only starter guns that make noise but can't cause serious injury.
Officers scouring the building overnight found several devices on the suspect, including two table-top propane gas canisters and two pipe bombs, NBC News reported Thursday.
Police told NBC News that they had given the building the "all-clear," but were still treating the area — where a man who identified himself as James J. Lee had held three people hostage — as a crime scene.
It remained closed overnight after Wednesday's standoff; police did not indicate whether employees would be permitted to return to work Thursday, NBC News added.
Police shot to death the man Wednesday at the building in suburban Washington, D.C. Authorities said the hostages were safe.
At least one device on the man's body went off when he was shot inside the building in suburban Washington, D.C., Montgomery County police Chief Thomas Manger said. Police had been trying to determine whether two boxes and two backpacks the gunman had also contained explosives.
Manger said SWAT officers shot the gunman about 4:50 p.m. EDT because officials "believed the hostages were in danger." The hostages — two Discovery Communications employees and a security guard — were unhurt after the four-hour standoff.
An NBC News producer who called the building to find out what was going on when he came on the line unexpectedly. He said, "I have a gun and I have a bomb. ... I have several bombs strapped to my body ready to go off."
NBC News informed Montgomery County authorities of the conversation as the producer spoke to the man for about 10 minutes. NBC News did not report the conversation until the hostage situation had been resolved.
Speaking to reporters, Manger would not release the man’s identity, but numerous law enforcement authorities gave NBC News the same name: James J. Lee.
Lee, 43, was a longtime protester at the building who was sentenced to six months of supervised probation for disorderly conduct in March 2008.
Manger said the suspect held the hostages in the lobby area of the first floor. He said police spent several hours negotiating with the armed man after he entered the suburban Washington building about 1 p.m.
Police department sources told NBC News that the suspect told negotiators throughout the ordeal that he was prepared to die. Only when the suspect pointed his weapon directly at the hostages did the Tactical Team commander determine they had to rush the lobby.
As the team ran in, the hostages rushed out, according to NBC News, citing police department sources. At that point, officer had a clear line of sight to shoot and kill the suspect.
The building in the close-in suburb of Washington was safely evacuated, including the Discovery Kids Place day care center, and none of the 1,900 people who work in the building were hurt.
'The planet does not need humans'
Lee appears to have , saying humans are ruining the planet and that Discovery should develop programs to sound the alarm.
"I want Discovery Communications to broadcast on their channels to the world their new program lineup and I want proof they are doing so. I want the new shows started by asking the public for inventive solution ideas to save the planet and the remaining wildlife on it," the alleged manifesto reads, adding:
"Nothing is more important than saving ... the Lions, Tigers, Giraffes, Elephants, Froggies, Turtles, Apes, Raccoons, Beetles, Ants, Sharks, Bears, and, of course, the Squirrels. The humans? The planet does not need humans."
Court records show that Lee was arrested Feb. 21, 2008, on the sixth day of a protest at the Discovery building. At the time of his conviction in March 2008, he was identified as being from San Diego.
Police were called to the scene when a crowd that had gathered began growing "unruly" as Lee threw thousands of dollars of cash into the air, some of it still in shrink-wrapped packages, police said at the time. (Lee was found not guilty of littering.) •
Lee said at the time that he experienced an "awakening" when he watched former Vice President Al Gore’s environmental documentary "An Inconvenient Truth."
Nathaniel Harrington, a former Discovery employee, told msnbc TV's Peter Alexander that he saw Lee outside the building during the 2008 protest.
"He was seen as something of a joke," Harrington said. "I hate to say it, but at the time we kind of half-joked about it because he could come back shooting. Nobody took it very seriously."
"As soon as I heard" the news Wednesday, "I knew it’s got to be Lee," he said.
Lee had been active in other online arenas, too, in pursuing his causes:
While his main domain, , is now a single page presenting his complaints, archives show that in the past he has used it to promote a contest to give away money and property in Hawaii "for the best TV show idea to save the planet."
In early 2008, a message board called was set up by a man calling himself Lee who uses a profile picture very similar to other photos of James Lee.
In a , the man, using the screen name misterfifteen, explains that he specifically targeted Discovery because he believes its identification with environmentalism was a sham:
"Discovery is hugely responsible for what is happening and their ineffective programming must be protested and dealt with. The time for pussy-footing around the subject is done. It's time to protest them until they start changing their stupid message. They ARE glorifying the damned fishermen who are overfishing the planet and I would think that you would see that for yourself instead of defending them."
‘Save the Planet’ TV show pitchThe man goes on to say that he approached Discovery with programming ideas at one point "even though I had a feeling that they were working for their own greedy ends.” Discovery officials “didn’t do anything," he writes.
The nature of that proposed programming can be gleaned from an undated pitch letter Lee sent to Discovery.
Calling himself "Mister Lee" and giving a Silver Spring address, Lee proposes "an idea for a reality-game show called 'Race to Save the Planet.'"
According to the letter, which msnbc.com retrieved from archives of unlinked material on his website, Lee says contestants "would come from all over to compete with each other and come up with ideas to save the planet. The idea here is to use human inventiveness to save the planet from the environmental destruction it’s facing. People competing can either have completely new ideas on how to save the planet, or they can build on another person’s idea and make that original idea better."
He concludes: "'Race to Save the Planet.' This show could very well save the planet."
Also pulled down sometime in the past two years was a page set up to protest Discovery. On it, he writes:
"If their 'environmental' shows are actually working, then why is the news about the environment getting worse? It should be getting better if they were doing their job and we should be seeing that reflected on the nightly news. But NO! The Discovery Channel is actually not about saving the planet, they are just another ‘green’ corporation whose real interests lies in MONEY! Products! Junk! Trash!"
'Chaotic' scene describedWednesday’s drama likewise played itself out online as scores of Discovery employees sought and gave information on Twitter and other social media services.
At the scene itself, helicopters and dozens of police cars patrolled the area, and most of the streets were blocked off.
"Someone over the P.A. said there’s a situation in the lobby, go back to your desks," Melissa Shepard, a Discovery employee, told msnbc TV. "So we all went to offices and crammed into offices and shut the lights off and listened to the news. Then someone knocked on the door and said we need to evacuate."
Shepard described initial confusion over the evacuation plan.
"The scariest was when they were telling us to go upstairs, then downstairs, then upstairs. I don’t know if it was safe," she said.
"The thing is we were hearing there were two people, then explosives, then hostages, then that people were shot. We kept hearing different stories. It was one thing after another."
"It’s pretty chaotic," Tariq Warner, a photographer for NBC station WRC-TV, said on msnbc. He said a woman ran past him screaming.
Discovery Communications reaches about 1.5 billion subscribers in more than 180 countries with the Discovery Channel, TLC, Animal Planet, Science Channel and Planet Green networks.