Suspect James Lee is seen in 2008. (Katie Gross)

A man upset with the Discovery Channel’s environmental programming who took three people hostage at gunpoint at the company’s headquarters Wednesday has been shot by police, officials said.

All three hostages are safe, police said.

Police believe the man is James Lee, 43, a federal law enforcement official told CBS News. Lee has protested at the Discovery Communications site before.

According to a story in The Gazette, which covers Montgomery County, Lee was arrested there in 2008 after throwing thousands of dollars in the air outside the building.

(Scroll down to watch a video of the suspect apparently throwing money in the air outside the Discovery Channel’s headquarters)

Who is James Lee?

Montgomery County Police Chief Thomas Manger said at 1 p.m. the gunman entered through the main entrance of the building wearing what seemed to be metallic canister devices strapped to his front and back and waving a handgun.

The man metallic canisters on his front and back that appear to explosives, though police could not confirm whether or not they are real is real.

“We’re going on the assumption that they could be explosive devices,” Manger told reporters. “That’s the only way we can proceed.”

Dolan said the company has unarmed security guards who won’t let anyone into the building without a badge.

Police have been talking to the suspect since about 2:20 p.m. ET. The man is holding an unconfirmed but “small” number of hostages, Manger said.

Manger said that there are no reports of injuries on the scene and that of the building’s 1,900 employees, “most of them are out,” though there may be a few remaining on the building’s upper floors. The gunman and hostages are on the ground floor near one of the building’s lobbies.

Montgomery County fire spokesman Capt. Oscar Garcia said three bomb technicians responded to the scene and several more were on the way.

The initial report was of a suspicious package that was possibly explosive, said Garcia, who also said no one had been injured. He said some employees had left the building.

Witnesses have reported that the man has fired multiple shots, though police have not confirmed those details.

Montgomery County police, SWAT teams, and explosives experts are on the scene and have set up a perimeter of roughly 200 yards around the building. The FBI and ATF are also on the scene.

A website registered to Lee criticized Discovery and announced plans for the protest in January 2008: “These guys have been very sneaky and deceptive as to their contribution to the planetary problems. Just look at their ‘new’ show about saving the planet, ‘Planet Green,’ to me, it’s just another show about more PRODUCTS to make MONEY, not about actual solutions. We can’t let them get away with doing it anymore.”

After his 2008 arrest, Lee said he planned the protest because Discovery’s programming had little to do with saving the planet. He was identified then as being from San Diego, Calif., although he gave a local address of a homeless shelter.

Police reports indicate he paid homeless people to join his protest and carry signs outside the building. He gave one individual $1,000 for what he considered a prize winning essay.

At one point, a crowd of more than 100 people gathered around Lee, 43, who referred to money as “just trash” and began throwing fistfuls of it into the air.

At the trial, he said he began working to save the planet after being laid off from his job in San Diego. He said he was inspired by “Ishmael,” a novel by environmentalist Daniel Quinn and by former Vice President Al Gore’s documentary “An Inconvenient Truth.”

A magistrate ordered a doctor’s evaluation for Lee, but court records do not immediately indicate the result. Lee was convicted by a jury and served two weeks in jail. He was also ordered to stay 500 feet away from Discovery headquarters.

Laura Fountaine, a Discovery employee, told CBS Radio News she was returning from her lunch break when she heard a gunman was in the building. She said there’s a daycare center located on the first floor of the building.

“I came out with a lot of the nursery babies; they had like cribs of babies that they were rolling out across the street,” said Fountaine. “I just couldn’t believe this was happening. This doesn’t happen. Everybody likes Discovery. Why would this be happening here?”

Melissa Shepard, 32, of Peterborough, N.H., a consultant who works there during the week, said she was on the third floor in a large room with several other workers when someone announced over a loudspeaker that there was a situation in the lobby and people should stay at their desks.

After some time, they were told to move to the other end of the building. She said she was among a dozen workers who huddled into an office, shut the door and turned off the lights.

Then she said someone knocked on the door and told them to leave the building. She said there was some confusion as they were told to go to an upper floor or down the stairs.

“Finally, I screamed, ‘tell us where we need to go…I just want to get out of there,'” she said. “I was shaking…I was like what do we do what do we do?'”

Adam Dolan, a sales director in Discovery’s education division, told The Associated Press by phone that he was heading to lunch with a co-worker when he heard there was a situation in the building.

He was told to go back up to the top floor, the ninth, and lock the door and turn off the lights. Eventually the workers were herded down a stairwell and told to go home.

“Everyone was very scared, but at the same time … I think people were calm and collected and responded as one would expect in this situation,” said Dolan, 28.

When he got to the bottom floor, he saw shattered glass near the company’s daycare and suspected it was broken to get the children out. He later got an e-mail that all the children were safe and had been taken to a McDonalds.

All major roads into Silver Spring have been sealed off.

Discovery Communications Inc. operates cable and satellite networks in the U.S., including The Discovery Channel, TLC and Animal Planet. Discovery shows include “Cash Cab” and “Man vs. Wild,” and TLC airs “American Chopper” and “Kate Plus Eight.”

Animal Planet also airs the controversial series “Whale Wars,” about attempts by environmentalists to disrupt the Japanese whaling industry.

The Discovery building was part of a major redevelopment of once-troubled Silver Spring during the 1990s.

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