Brian Healion, 33, of Upper Darby, previously pleaded guilty to one count of civil disorder in February, said the US Attorney's Office.
Court documents alleged Healion was a member of the Philadelphia "Proud Boys" chapter and "traveled to Washington, D.C., to protest Congress's certification of the Electoral College vote for the 2020 presidential election."
Authorities claimed Healion marched with 100 other members of the group toward the Capitol building from the Washington Monument. They were accused of shouting "Treason" and "Don't make us go against you" to a group of Capitol police officers at the scene.
The marchers "crossed over and trampled bike rack barriers in their advance toward the Capitol building," and Healion at one point "yanked (a bike rack) away from a Metropolitan Police Department Officer" at the police line, said the US Attorney's Office.
Once inside the building, prosecutors claimed he and others posed for pictures in a US Senator's office before leaving after 20 minutes.
Healion was arrested by the FBI on Dec. 10 of that year, authorities said.
In addition to the 100-day sentence, he was ordered to serve 36 months of supervised release and pay a $2,000 fine.
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