Transcript for Washington readies for inauguration as security concerns remain high
Hey, good morning. T-minus four days until the inauguration of President-Elect Joe Biden and we begin with a sweeping security crackdown in Washington, D.C. The national mall temporarily shut down closed to the public for at least a week. And four bridges connecting D.C. To Virginia also closed. The FBI is now warning about the potential threat of improvised explosive devices being used in upcoming protests saying the danger posed to law enforcement officers and the general public is, quote, substantial. Intelligence officials also warning the siege at the capitol emboldened extremists and could be part of an ongoing trend of radical domestic groups exploiting lawful gatherings. ABC's Kenneth Moton is in Washington with more on what's being done to combat the threat. Kenneth, good morning. Reporter: Good morning, guys. From the white house to the capitol this is what we're seeing, barricades everywhere especially downtown in D.C. The U.S. Secret service is running the show here but the agency also says in every state it's pursuing potential leads as it works to fortify Washington, D.C. This morning, we're just days away from the largest security effort ever to protect an the nation's capitol a fortress. Checkpoints in place and barricades down, armed members of the National Guard on duty. The FBI is worried about the substantial threat of improvised explosive devices on inauguration day and the ongoing threat to political leaders. Authorities also concerned that January 6th attack on the capitol has emboldened domestic extremists. I don't know if anyone has raised their hand to say we are coming, we will be there, but we are preparing as if they are. Reporter: Security tight days before the big event and it's only going to get tighter. The city's mayor and federal officials telling us there's a major responsibility to get this right. Several states also on high alert especially the battleground states from the November election like Michigan and Wisconsin. This as we learn about the close call for vice president Mike pence. "The Washington post" reports secret service rushed pence out of the senate chamber one minute before pro-trump rioters reached the second floor. The mob led away from the chamber by a lone officer now hailed as a hero. House speaker Nancy Pelosi is ordering an immediate review of capitol security, including whether any members of congress gave building tours to rioters the day before. If it is found that members of congress were accomplices to this insurrection, if they aided and abetted the crime, there may have to be actions taken beyond congress. Reporter: As arrests continue authorities are concerned about the large number of pro-trump rioters with ties to law enforcement and/or the military. Suspect Jacob chansley who allegedly left a note on pence's desk that read, it's only a matter of time, justice is coming, served in the military. Prosecutors accusing air force veteran Larry Brock of carrying zip ties to take hostages. One of two rocky mountain, Virginia police officers arrested Jacob fracker is a corporal in the Virginia National Guard. New video shows the violence at the capitol. A police officer shoved, punched and yelled at buy a rioter and this moment when officer fanone beaten by the angry mob. It looked like a medieval battle scene. Some of the most brutal combative's ever encountered. Reporter: Another D.C. Officer Daniel hodges thought he would die in this doorway. The FBI releasing a photo of the man they say pinned hodges. That many people yelling in the tunnel is extremely loud, you know. It was just a sensory overload but I knew is that no one was Reporter: Backup is now here, 25,000 National Guard troops are expected by inauguration day and they could use deadly force if necessary. At least ten states have activated national guards in their capital cities. Eva? Kenneth, that video hard to watch.
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