As hundreds of National Guard troops started to arrive in Washington, there were no cars or scooters all through downtown and seemingly no tourists around the area on Wednesday. Only the occasional jogger and multiple construction crews at work.

According to an Associated Press report, a group of uniformed National Guard troops was deployed two blocks from the White House and headed into a hotel as the state of Washington imposed a lockdown that will last until the Jan. 20 inauguration.

Chief of the National Guard Bureau Army Gen. Daniel Hokanson told Vice President Mike Pence at a briefing that the number of National Guard troops coming to Washington to assist in security has increased to about 21,000.

Officials said that the number could grow as law enforcement authorities continue to review the ongoing threats as Inauguration Day nears.

"They are under the command and control of Maj. Gen. William Walker, the Commanding General of the D.C. National Guard, and are providing security, communications, logistics and coordination with all supported agencies," Hokanson said in a Military Times report.

Hokanson noted that their first priority is to protect people and property and the safety and wellbeing of their National Guard personnel and their families.

The chief of the National Guard said he visits these men and women every night, adding that they understand the importance of the mission.

Washington Mayor Muriel Bowser said that they are clearly in "uncharted waters."

Related story: Possible Armed Protests To Erupt Across 50 States, FBI Memo Warns Law Enforcement

Role of the National Guard

The National Guard's assistance in Washington came after the deadly riot at the U.S. Capitol by President Donald Trump's supporters.

The National Guard is expected to support civil authorities, protecting the life, property of U.S. citizens, and protecting critical U.S. infrastructure.The National Guard is also expected to provide humanitarian assistance during disaster response and domestic emergencies.

The troop's length of the mission may vary. Defense Department officials were authorized to deploy the Guard for up to 30 days for the inauguration and surrounding protests.

Pentagon authorities have approved requests to have some Guard troops armed with either long guns or handguns, especially those Guard members deployed to the U.S. Capitol. 

National Guard Activated after FBI Warning of Armed Protests

A memo from the Federal Bureau of Investigation (FBI) warned federal law enforcement agencies across the country of armed protest planned in all 50 states from Jan. 6 through at least the Inauguration Day.

The intel is being taken seriously by officials in light of the violence that took place at the Capitol last week. Leaders were briefed by officials responsible for the security of the Pennsylvania State Capitol.

House Democratic Leader Joanna McClinton said that many members had contacted her, especially last Wednesday, as they saw the nation's capital under terror, according to an ABC 6 report.

The FBI also released at least one other bulletin before the riots that took place. The FBI warned on Dec. 29 of the possibility for the armed demonstrators targeting lawmakers.

The bureau said that their standard practice is to not comment on certain intelligence products. However, they are supporting state, local, and federal law enforcement partners with maintaining public safety.

Meanwhile, Delta, Alaska, American, and United Airlines announced that they would not allow travelers flying to Washington area airports to check firearms on its flight ahead of the inauguration day.

According to a Reuters report, Delta chief executive Ed Bastian said that they had placed passengers on a no-fly list for their involvement in disruptive incidents.

National railroad service Amtrak said that it had also heightened security measures, such as adding police officials on the train.

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