Floyd Ray Roseberry of North Carolina "was just taken into custody moments ago," Capitol Police Chief Thomas Manger told reporters at 2:30 p.m. "He's been moved away from the scene."
Manger then left without answering questions.
Roseberry livestreamed on Facebook during the standoff -- which cleared all area buildings and brought a huge law enforcement response -- before it was taken down.
"We're livin' in a free country, Joe. The choice is yours," Roseberry said, addressing President Biden. "If you wanna shoot me and take the chance of blowin' up two and a half city blocks, cause that toolbox is full, ammonium nitrate, it's full."
He then showed a can of what appears to be shotgun flake powder.
"If you don't think it's real gunpowder in there boss man, there's gunpowder in there, and this is some of the strongest sh*t you can get," Roseberry said in a clip from the Facebook livestream video posted on Twitter by Senior Justice Reporter Ryan J. Reilly of the Huffington Post.
"I'm telling you, Biden, if these window pop, this bomb goes," he added.
Roseberry, of Grover, North Carolina, then claimed that there were four other bombs somewhere in the district.
"I don't know where they are at," Roseberry said. "We all came in different ways, but we all came from the same place."
The clips below were posted by HuffPost's @Ryan J. Reilly:
"You said if you could anything to save one life, one life, you said you'd do it. Well, you got a chance," Roseberry says, addressing the president. "I want to go home... I want to go home and see my wife....I don't wanna die, Joe, I wanna go home,"
"If you blow my truck up, hey, it's on you, Joe. I'm ready to die for a cause."
The "safe a life" comment may be a reference to something Biden said as vice president during an argument for gun control in 2013.
“As the president [Obama] said, if your actions result in only saving one life, they’re worth taking," Biden said at the time. "But I’m convinced we can affect the well-being of millions of Americans and take thousands of people out of harm’s way if we act responsibly.”
Roseberry drove the black pickup with no license plates onto the sidewalk in front of the Library of Congress and claimed to have a bomb around 9:15 a.m., Manger said.
The officer saw "what appeared to be a detonator" in his hand, the chief said during a noontime news conference.
Authorities didn't know whether the threat was genuine or not but were erring on the side of caution, Manger told reporters.
Congress is on recess, "but people are still working" in the buildings, which were evacuated, the chief said.
A photo posted on Twitter shows the bald, bearded Roseberry holding a cellphone and looking out the window of the truck with dollars bills scattered around that a witness said he tossed out the window.
He was live-streaming on Facebook during the incident, but it was eventually taken down.
Roseberry reportedly made references to the fall of Kabul, the United States' giving the Taliban military equipment and being "shadow banned" by Facebook, and told "Biden and Nancy" that they should leave Washington unless they "want to hear people scream."
"Labor Day weekend they gonna know the motherf*ckin' South was there," he also reportedly said, as well as predicting that President Trump will return to office after Biden is driven out -- then will pardon him.
It was unclear how Roseberry got past various checkpoints when he drove up on the sidewalk. The FBI and ATF joined district police, firefighters and EMS at the scene.
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