UPDATE: Capitol Hill bomb threat suspect identified, taken into custody following hours-long standoff

Update 8/19/2021, 2:29 p.m. ET: Capitol Police announce that the suspect, 49-year-old Floyd Roseberry of North Carolina, has been taken into custody without incident. Authorities say that Roseberry recently suffered several "losses," pointing to the death of his mother and more.

Police say they have no indication that Roseberry was acting in conjunction with others, but that the investigation into the incident will continue until full facts are clear.

Authorities say they are working with the U.S. attorney to determine charges.

A full news release is forthcoming.

Update 8/19/2021, 2:21 p.m. ET: NBC's Pete Williams reports that the suspect has surrendered and police are taking him into custody.

More information on the suspect's identity to come upon official confirmation.

Update 8/19/2021, 1:22 p.m. ET: CNN reports that negotiators are still working with the suspect and trying to determine a motive for the threat.

Capitol Police Chief Tom Manger says, "We don't know what his motives are at this time."

Update 8/19/2021, 12:24 p.m. ET: NBC's Pete Williams reports, "It happened when the driver of a black pickup struck stopped the vehicle in front of the main Library of Congress building known as the Jefferson Building ... which is about a block away from the U.S. Capitol. He claims to have a propane tank inside the vehicle and claims to be holding a detonator in his hand. Now the authorities have not actually seen any explosive material at all."

CNN reports that US Capitol Police Chief Tom Manger issued the following statement on the incident:

Around 9:15 am this morning, a man in black pickup truck drove onto the sidewalk in front of the Library of Congress near First and Independence Southeast. We responded to a disturbance call. The driver of the truck told the responding officer on the scene that he had a bomb and what appeared, the officer said, appeared to be a detonator in the man's hand. So we immediately evacuated the nearby buildings.

Update 8/19/2021, 11:35 a.m. ET: CNN's Whitney Wild reports that authorities on the scene are "negotiating with [a] suspect," who is reported to have arrived at the scene in a pickup truck without license plates.

"CNN reported earlier that negotiators were being sent to talk to a man in the truck after responding to claims of suspected explosives in a vehicle near the US Capitol," the outlet noted.

Update 8/19/2021, 11:37 a.m. ET: The Federal Bureau of Investigation has joined the Capitol Police in investigating the active bomb threat.

In a Thursday morning tweet, the FBI wrote, "The FBI Washington Field Office's National Capital Response Squad is responding with our partners, including @CapitolPolice to reports of a suspicious vehicle and bomb threat near the Library of Congress.

Original story continues below

U.S. Capitol Police on Thursday announced an "active bomb threat" investigation near the Library of Congress, according to the Associated Press, prompting nearby Capitol Hill buildings including the Cannon House Office Building to be evacuated.

What are the details?

Police on Thursday morning announced that officers were responding to reports of a suspicious vehicle near the Library of Congress and urged all people to stay away from the area.

The news agency reported that police said there is a possibility of explosives inside the vehicle.

In a tweet, the U.S. Capitol Police said, "MEDIA ALERT: This is an active bomb threat investigation. The staging area for journalists covering this situation is at Constitution and First Street, NW, for your safety. Please continue to avoid the area around the Library of Congress."

"This is an ongoing investigation," the department added. "We are monitoring this situation closely and will update this account as we get information we can release."

What else?

According to WTTG-TV, Capitol Police told the Associated Press that "investigators on the scene were working to determine whether the device was an operable explosive and whether the man in the truck was holding a detonator."

The officials, according to the station, were not authorized to publicly discuss the matter.

The station reports that the following streets have been closed:

• Independence Ave between 3rd St. SW to 2nd St SE
• Constitution Ave between 3rd St. NW and 2nd St. NE
• East Capitol NE between 1st St NE and 2nd St SE

This is a developing story and will be updated as events warrant.