A throng of protesters furious about the not-guilty verdicts for a St. Anthony police officer in Philando Castile’s death faced off with helmeted law enforcement officers late Friday after shutting down Interstate 94 in St. Paul.

The freeway confrontation, which involved several hundred people, came after a larger peaceful protest at the State Capitol, followed by a twilight march after which many protesters spun off and flooded the freeway, despite protest organizers’ entreaties not to do so. By 12:30 a.m., only a few protesters were left, slowly herded onto a freeway ramp by officers. Minutes later, the arrests began, with 18 taken into custody by the State Patrol.

They were to be booked at the Ramsey County jail. St. Paul police, who also responded, made no arrests, according to a department Twitter account.

In the afternoon, at least 2,000 people gathered in a misty rain on the Capitol steps in a show of grief and outrage. John Thompson, a friend of Castile, screamed into the microphone, “Minnesota is not nice! … We are living in a war town,” before breaking into tears. “You murdered my friend,” Thompson said, referring to the state of Minnesota.

Nekima Levy-Pounds, who is running for Minneapolis mayor, told those in the crowd they had reason to be outraged by the verdict.

“We have a right to gather at the seat of power and ask for justice,” she said. “They’re making all of these cosmetic changes [to the Capitol] … in a broken, ugly evil system.”

In a written statement issued before the rally, organizers said the Yanez verdict “is just the latest round of injustice delivered by a system that has always failed to hold police accountable for their crimes.” Organizers included Black Lives Matter Twin Cities Metro, Communities United Against Police Brutality and Twin Cities Coalition for Justice for Jamar.

Although the verdict was “a tremendous blow,” organizers said, Yanez was the first police officer in Minnesota history to be charged with fatally shooting a citizen — a case that went “further than any other in the fight against police terror.”

As many in the crowd raised fists, speakers urged the crowd to take to the streets. “Some people will tell you protest don’t work,” said activist Mel Reeves. “They wouldn’t have tried to put on the show trial if we hadn’t protested,” referring to the marches and protests immediately after Castile was shot last summer.

“Save your tears. I’m not crying, I’m going to fight,” Reeves said. “If we want to win, we got to raise some hell. … They shot this man because he was a black man.”

A giant spray-painted canvas of Castile wearing a crown that read “Long Live the King” served as a backdrop for the rally. A chorus emerged: “No justice, no peace!”

Demonstrators held signs that read “Justice is dead” and “On Trial: The System. Verdict: Guilty!”

Kenny Washington sat near the Capitol steps holding a Black Lives Matter sign as speeches increased in anger. Washington blames racial profiling for being stopped dozens of times by police, and the encounters led to conversations with her son about how to behave around police.

“You have to prepare them for the real world,” she said of her son, now 16. “I worry incessantly. Even if you follow the law to the T, are you going to end up dead?”

The Yanez case will further tarnish relations between law enforcement officers and black community members, Washington said. “I’m just wondering when our voice will be heard. We can’t keep saying the same thing.”

As the sun set, the crowd gathered behind banners and marched down University Avenue, temporarily shutting down the Green Line. “Whose streets? Our streets!” they chanted. “No justice, no peace; prosecute the police!”

Organizers urged protesters to stay off of nearby I-94, but at about 10:30 p.m., about 500 people raced onto it and blocked lanes in both directions. Many cars that were halted by the protest turned around and went the wrong way on the freeway in both directions, seeking the nearest exits.

Passions and tension ran high, but as the night wore on and law enforcement officers slowly herded them off the freeway, many people left.

By 12:30 a.m., helmeted state troopers and St. Paul police officers had pushed the few dozen remaining protesters onto an exit ramp. They repeatedly ordered them to disperse, and just before 1 a.m., patrol officers arrested the 18 people, including a working reporter, City Pages’ Susan Du.

Those arrested were herded onto Metro Transit buses for transport to jail.