Bill O'Reilly publicly rebuked President Trump, his longtime friend, in the wake of the violent attack on the U.S. Capitol.

"President Trump’s failure to tamp down the angry protestors supporting him in Washington has destroyed his legacy," the former Fox host tweeted Saturday. "Our divided nation turns to you, @JoeBiden. Defuse it. As best you can."

In a follow-up tweet, O'Reilly said that he didn't believe that Trump "encouraged" Wednesday's violent riots, as many Democratic and Republican leaders have charged.

"The President is smart enough to understand that a calculated violent attack on Congress in his name would destroy him," the "No Spin News" host said.

O'Reilly recently wrote a book on the president. "The United States of Trump: How the President Really Sees America," published in 2019, was an "intimate" look at Trump "from a writer who has known the president for thirty years," publishing materials said.

Trump defended O'Reilly amid sexual misconduct allegations in 2017, before the conservative commentator was ousted from the Fox News Channel.

Trump has been quiet Saturday after Twitter announced Friday evening that it had permanently suspended the president's account.

"After close review of recent Tweets from the @realDonaldTrump account and the context around them -- specifically how they are being received and interpreted on and off Twitter -- we have permanently suspended the account due to the risk of further incitement of violence," Twitter wrote in a statement.

Trump's final tweet said he would not be attending Biden's inauguration.

After Twitter's announcement, Politico reported that the president went "ballistic" and “[scrambled] to figure out what his options [were].”

Hours after his suspension, Trump released a statement criticizing the ban and teasing a possible new platform.

"I predicted this would happen," he wrote in part. "We have been negotiating with various other sites, and will have a big announcement soon, while we also look at the possibilities of building out our own platform in the near future. We will not be SILENCED!"

"Twitter is not about FREE SPEECH. They are all about promoting a Radical Left platform where some of the most vicious people in the world are allowed to speak freely," he added.

Trump had attempted to post the same statement on Twitter using the official @POTUS account, but the platform deleted the thread, saying users who are banned cannot post from other accounts.

Secretary of State Mike Pompeo blasted Twitter Saturday, comparing the ban of the president to something that would happen in China.

"Silencing speech is dangerous. It’s un-American. Sadly, this isn’t a new tactic of the Left. They’ve worked to silence opposing voices for years. We cannot let them silence 75M Americans. This isn’t the [Chinese Communist Party,]" he wrote on Twitter.

Former Ambassador to the United Nations Nikki Haley also took to the platform to draw a comparison to China writing, "Silencing people, not to mention the President of the US, is what happens in China not our country. #Unbelievable"

The White House announced Thursday that the president planned to spend the weekend at Camp David before notifying reporters that the trip was canceled. The president has nothing on his schedule Saturday.

-ABC News' Mark Osborne and Conor Finnegan

Two more senior Trump administration officials resigned following the president's remarks Wednesday and the violent assault on Capitol Hill that ensued, ABC News confirmed Saturday.

Anthony Ruggiero, the senior director for counterproliferation and biodefense on the National Security Council, resigned Thursday, a source familiar with the situation confirmed. He joins deputy national security adviser Matt Pottinger and other senior NSC officials who quit over Trump's comments.

The State Department lost its first assistant secretary over the week's events, too. Dr. Chris Ford, the top diplomat for arms control, resigned Friday, a second source familiar with the situation confirmed.

The Washington Post reported that Ford originally announced his departure Wednesday morning but sent a follow-up note to staff Friday resigning immediately and condemning those in the administration who "are willing to condone, or even to incite, violent insurrection against the country I hold dear and whose Constitution I have taken a sacred oath to support and defend" -- a tacit reference to Trump.

-ABC News' Conor Finnegan

Republican former Maine Sen. Olympia Snowe has called on the president to resign following Wednesday's violent storming of the Capitol by a pro-Trump mob.

"President Trump should resign from office now to allow our nation to begin to heal and prepare for the transition to the Biden presidency," Snowe tweeted Saturday.

The former senator joins other Republicans, like Sen. Lisa Murkowski, R-Alaska, and Rep. Adam Kinzinger, R-Ill., in calling for the president to leave his post or for his removal before his term ends on Jan. 20.

Known as a moderate, Snowe served as senator from Maine between 1995 and 2013.

-ABC News' Benjamin Siegel

Three days after Capitol Police Officer Brian Sicknick died defending the Capitol against insurrectionists the White House lowered the U.S. flag to half-staff.

The decision to lower the flags came hours after Capitol Police also announced the off-duty death of Officer Howard Liebengood. The circumstances of his death have not been made public.

The U.S. attorney's office in Washington opened a federal murder investigation into the death of Sicknick, who died Thursday night after suffering injuries in the violent siege on Capitol Hill, three law enforcement sources confirmed to ABC News.

The investigation is being conducted jointly between the FBI and the D.C. Metropolitan Police Department, with cooperation from U.S. Capitol Police.
Acting Attorney General Jeffrey Rosen said in a statement that the Department of Justice "will spare no resources in investigating and holding accountable those responsible."

-ABC News' Elizabeth Thomas