Today: One year anniversary of the attack on the U.S. Capitol

(KYMA, KECY/ NBC News) - Thursday marks one year since the attack at the U.S. Capitol where a large crowd, loyal to then-President Donald Trump, laid siege to the building last year in an effort to overturn Trump's defeat in the 2020 election.

According to White House officials, President Biden plans to speak inside the Capitol building Thursday to talk about the potential "singular responsibility" former President Donald Trump had in the riot.

Vice President Kamala Harris is also slated to deliver a speech, where she will talk about the broader implications of the attack.

Congress is also planning to address the anniversary, starting with a moment of silence on the house floor and then several lawmakers who were trapped in the chamber as rioters made their way inside the building will recall their experiences from that day and reflect on what happened.

Trump was expected to hold a news conference on the anniversary, but it was abruptly canceled after allies warned it could cause unnecessary problems for republicans.

For months now, a House Select Committee has been entrenched in a sweeping investigation of the attack.

And they are working to:

• Establish the definitive narrative of what happened that day, and what led up to it
• Offer a series of recommendations to prevent it from happening again
• And-- if they discover criminal activity -- send it to the department of justice.

So far the committee has conducted:

• Interviews with more than 300 people
• Collected around 35,000 documents
• And issued more than 50 subpoenas
• It's also been seeking phone records and bank records

In the coming months:

• There could be prime time public hearings
• Then in the summer -- we could see an interim report
• Ahead of the 2022 midterm elections in November, it could be all wrapped up.

Also on this anniversary, Arizona Senator Mark Kelly released a statement saying in part, "despite this unpatriotic attempt to silence the voices of Arizona voters, democracy prevailed."

He also applauded the bravery of law enforcement and Capitol police on that day.