"Stop the count!" the Trump supporters chanted in Detroit. "Stop the steal!" they said in Phoenix.
The protests came as the president insisted without evidence that there were major problems with the voting and the ballot counting, especially with mail-in votes, and as Republicans filed suit in various states over the election.
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Wearing Trump gear, the Phoenix protesters filled much of the parking lot at the Maricopa County election center, and members of the crowd chanted, "Fox News sucks!" in anger over the network declaring Joe Biden the winner in Arizona.
Rep. Paul Gosar, an Arizona Republican and staunch Trump supporter, joined the crowd, declaring: "We're not going to let this election be stolen. Period."
However, observers from both major political parties were inside the election center as ballots were processed and counted, and the procedure was live-streamed online at all times.
Several sheriff's deputies blocked the entrance to the building. And the vote-counting went on into the night, Maricopa County Elections Department spokeswoman Megan Gilbertson said.
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