Updated 3:15 p.m. ET
Local and federal security officials expect about 20,000 National Guard members to be involved in securing Washington, D.C., for President-elect Joe Biden's inauguration next week.
"I think you can expect to see somewhere upwards of beyond 20,000 members of the National Guard that will be here in the footprint of the District of Columbia," Washington Metropolitan Police Chief Robert Contee said on Wednesday.
It represents an uptick in National Guard troops that will be deployed to the area. Army Times reported earlier this week that the Pentagon had authorized 15,000 National Guard members to be sent to the District for the inauguration.
Contee said the inauguration has been designated as a "national special security event," adding the final numbers of troops would come from the Secret Service and leaving open the possibility the numbers could fluctuate.
The exact number to be deployed is still being worked out by the Secret Service, the lead agency on inauguration security, and others, a U.S. official told NPR's Pentagon reporter Tom Bowman. The official, who requested anonymity because they were not authorized to speak to reporters, said the number of National Guard members to be deployed is up to 20,000.
The troops will be coming from nearly all states, Bowman reported, adding that only those who are either military police or have law enforcement experience will be armed.
Others will have access to their weapons but not carry them, and it remains unclear where the troops will deploy at the U.S. Capitol, according to the U.S. official.
President Trump issued a statement Wednesday urging supporters to commit "NO violence," citing unspecified reports on future demonstrations.
"In light of reports of more demonstrations, I urge that there must be NO violence, NO lawbreaking and NO vandalism of any kind," Trump said. "That is not what I stand for, and it is not what America stands for. I call on ALL Americans to help ease tensions and calm tempers. Thank You."
Presidential inaugurations are always massive security operations, but Biden's inauguration on Jan. 20 is facing heightened security concerns following last week's breach of the U.S. Capitol that left five people dead, including a Capitol Police officer.
These security moves come as the House of Representatives voted Wednesday to impeach President Trump a second time. The resolution charged him with "incitement of insurrection." National Guard troops are already patrolling the hallways of Congress, some carrying military assault rifles.
It was a startling reminder that just a week ago rioters attacked the building, overrunning Capitol Police in an attempt to block lawmakers from confirming Biden's Electoral College victory.
Since the siege, some members of Congress, including Rep. Jason Crow, D-Colo., an Iraq and Afghanistan veteran, have requested that Army Secretary Ryan McCarthy review backgrounds of any National Guard troops involved in inaugural security.
Crow tweeted over the weekend that he spoke with McCarthy and expressed "concerns about reports that active duty and reserve military members were involved in the insurrection."
Crow added that McCarthy said he "agreed to take additional measures."