Michigan, Virginia, Wisconsin, Pennsylvania and Washington are among the states that have activated their National Guards to strengthen security.
Abandoned by some in his own party and without his Twitter account, Trump could do nothing but watch history unfold on television.
It marked a stark contrast to the first time Trump was impeached in December 2019 over the Ukraine scandal, which was not supported by a single House Republican.
The lawmakers said Trump “demonstrated that he will remain a threat to national security, democracy and the Constitution if allowed to remain in office.”
GOP opposition to impeaching Trump began crumbling at the party's upper echelons on Tuesday as the No. 3 House GOP leader said she would vote to impeach Trump.
The FBI warned law enforcement agencies ahead of last week's breach of the U.S. Capitol about the potential for extremist-driven violence, U.S. officials said on Tuesday.
Twitter ended Trump's nearly 12-year run on the platform on Friday.
The Dow and the S&P 500 soared to all-time highs on Wednesday, but pared earlier gains after protesters stormed the U.S. Capitol.