WASHINGTON — A far-right extremist group leader was sentenced on Friday to more than five years in prison for repeatedly assaulting police officers with makeshift weapons during a mob’s attack on the U.S. Capitol over three years ago.

Scott Miller, who helped lead a Proud Boys chapter for Maryland and Washington, D.C., coordinated with other group members before they invaded the Capitol on Jan. 6, 2021, according to federal prosecutors. Miller, 33, attacked police seven different times with weapons, including a bottle, a stick and poles.

Notes found on Miller’s cellphone indicate that his white supremacist ideology and antisemitic views influenced his decision to storm the Capitol, a prosecutor wrote in a court filing. He expressed his intent to “fight” in order to protect “White America,” the filing says.

U.S. District Judge Tanya Chutkan, who is overseeing former President Donald Trump’s election interference case in Washington, said an attack like the Jan. 6 insurrection “can happen again” in the U.S.

“Extremism is alive and well in this country,” she said before sentencing Miller to five years and six months behind bars.

Miller apologized for assaulting police at the Capitol. He acknowledged that he embraced extremist ideologies before the Capitol riot, but told the judge that he is “reforming” himself.

“I am not a violent or hateful person despite some of the things you’ve seen,” he told Chutkan.

Investigators found Nazi paraphernalia and memes promoting racially motivated violence when they searched Miller’s Millersville, Maryland, home and his phone. A photo found on Miller’s phone shows him posing and smiling next to a news story describing the drowning of migrants, prosecutors said.

Authorities also found a shirt that Miller wore for Halloween to dress up as Derek Chauvin, the white Minneapolis police officer convicted of murdering George Floyd, a Black man, in the summer of 2020. Miller posed for a photo wearing the costume while kneeling on the floor. Chauvin pressed a knee on Floyd’s neck for over nine minutes.

Chutkan said the extent of Miller’s violent ideology and the racist, antisemitic material stored on his phone left her questioning whether Miller is genuinely remorseful or capable of such a rapid transformation.

“They don’t just arrive there by some random algorithm,” said the judge, who read aloud some of the most hateful messages.

Chutkan has been one of the toughest punishers of Jan. 6 defendants. Miller’s prison sentence is the longest that she has handed down so far in 45 cases, according to an Associated Press review of court records.

Prosecutors recommended a prison sentence of five years and 11 months for Miller, who was arrested in December 2022. He pleaded guilty in January to assaulting a police officer with a dangerous weapon.

“Miller’s participation in the riot — a riot that disrupted the peaceful transfer of power — was particularly egregious, given his multiple and repeated violent attacks on police officers and his coordination and planning with other members of the Proud Boys,” Justice Department prosecutor Kaitlin Klamann wrote.

In 2019, Miller was arrested on charges of disrupting a “Drag Queen Story Time” for children at a library in his Maryland hometown, The Baltimore Sun reported. Miller was accused of shouting at a performer and shoving a library board member who tried to intervene.

“While these charges were ultimately dropped, Miller’s actions on this occasion serve as further proof that Miller is willing to use violence to enforce his personal beliefs,” Klamann wrote.

In the days leading up to the Jan. 6 riot, Miller and other Proud Boys members discussed their plans for that day and the possibility of violence, prosecutors said. Miller arrived at the Capitol after the riot erupted, wearing gloves with plastic knuckles, ski goggles and a military-style backpack.

He joined the mob attacking police officers guarding a tunnel leading to an entrance on the Capitol’s Lower West Terrace, where some of the most brutal violence occurred. Picking up a pole, he charged at police and repeatedly struck an officer with it.

After throwing several objects at police, Miller picked up another pole and struck at least two officers several times. He also grabbed a shield from police officers and handed it to other rioters in the crowd outside the Capitol.

Miller is ashamed of his conduct on Jan. 6 and cut ties with the Proud Boys about a month after the riot, defense attorney Elizabeth Mullin said in a court filing.

“He disavows the group and the principles it stands for,” she wrote.

Mullin said there is no evidence that Miller planned to attack police.

“Regrettably, like so many others there that day, he became carried away by the frenzy of the crowd, which had been whipped into a fervor by Mr. Trump and the other rally speakers,” she wrote.