Transcript for Green zone perimeter established in Washington, DC
And it is a far different scene in Washington, D.C. Where a green zone perimeter has been established, roads shut down and because of that video you just saw, the National Guard scouring for explosives and extremists, the incoming administration moving forward with the outdoor inauguration, and ABC's Kenneth Moton is there tonight. Reporter: Tonight, extraordinary security in the nation's capital, officials taking no chances, military reinforcements arriving by the planeload. National Guard troops coming from every corner of the U.S. This mission is about protecting our republic itself. You're going to play a critical part at a time when our nation is in great need. Reporter: The 25,000 troops in this city by the inauguration have their orders, watch for potential threats, look for explosives, protect the capitol. Authorities say domestic extremists pose the most likely threat. How serious is our country going to take domestic white extremism, and I think what we saw here last week is that we didn't take it seriously enough. Reporter: Tonight the large security perimeter or green zone already tested. At least three people arrested in separate incidents including two men carrying guns and ammunition. Tonight the guard setting up 46 cots inside the capitol, but the man tapped to review the security failures there saying those troops can't be a permanent fixture. We can't afford, nor should we want to have 20,000 guard troops permanently stationed in D.C. The fixes are there, how we harden that capitol to make sure this never happens again. And we all hope so. Kenneth Moton joins us from Washington. Despite the security concerns, President-Elect Biden's team is moving forward with an outside inauguration? Reporter: That's right, Tom. Biden's team says they're preparing for any scenario, but they believe watching Biden take the oath on those same steps where the pro-trump riots occurred will send an important visual message about the resilience of this democracy. Tom. Kenneth Moton live again in the nation's capital for us tonight. Kenneth, thank you.
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