Thousands of demonstrators blocked streets and rallied across the Twin Cities on Tuesday, capping a sometimes bitter — and at one point violent — day of protests in reaction to Monday's Ferguson, Mo., grand jury decision not to indict a police officer in a fatal shooting.

A car plunged into a group of protesters and struck a 16-year-old girl outside a Minneapolis police station near E. Lake Street and Minnehaha Avenue. The incident was caught on a Star Tribune video. The victim was taken to a hospital with minor injuries, police said.

The driver, a 40-year-old man from St. Paul, was questioned, and Minneapolis police said they're investigating. The man's mother said that he was coming home from work and "he didn't even know what was going on" when he encountered the crowd blocking the intersection.

A later video showed a second vehicle, a white van, trying to get through the crowd. One protester flung himself on the van as it tried to pass.

In St. Paul, about 200 protesters gathered Tuesday night on the steps of the State Capitol and marched in the biting cold for several miles along University Avenue. The march disrupted traffic, but no other incidents were reported.

John Ward, 33, of Minneapolis, attended with his fiancée. "We want to show that peaceful protest is the norm," he said.

In the Lake Street incident, a Subaru station wagon lurched into the crowd around 4:30 p.m. with its horn blaring as the rally swelled to more than 1,000 demonstrators. When protesters didn't clear a path, the driver knocked down a girl. The crowd erupted in screams and some people jumped on the hood of the car and violently pounded on the windshield and windows.

The victim was quickly pulled clear and later whisked away by an ambulance.

Earlier in the day, several hundred University of Minnesota students and community activists gathered outside Coffman Union to protest the grand jury decision.

4½ minutes of silence

Organizers from the U's Black Student Union asked the crowd to observe 4 ½ minutes of silence, symbolizing the 4 ½ hours Brown's body lay on the ground after being shot.

The group demanded a meeting with U President Eric Kaler and Greg Hestness, chief of the university's police force, to discuss what they deemed to be an unjust policy of reporting a suspect's race in crime alerts that are dispatched to students and media.

The protesters later marched across campus, chanting "Hands up, don't shoot," "No justice, no peace," and "Shut it down" — bedrock chants that emerged after Brown's death.

Late Monday, Valeria Silva, superintendent of St. Paul public schools, tweeted, "No indictment for officer Wilson! Very sad day in America. How do I explain this to my black students?"

The tweet prompted criticism, including a rebuke from the St. Paul Police Federation calling the comment "ignorant." Silva deleted the tweet and on Tuesday, she apologized for it.

'Proud of our students'

Minneapolis School District spokesman Stan Alleyne said there were peaceful protests at several high schools and that participants would not be disciplined "as long as the protest remains peaceful." Later on Twitter, Alleyne wrote: "We are proud of how our students are handling themselves."

One of the South High protest organizers, junior Thomas Bates, said up to 400 students filled the commons area of the south Minneapolis school for about an hour to show their dismay with the outcome of the case.

About 10:30 a.m., nearly half of those students left the school and most walked about three-fourths of a mile to the police station, where some took turns with a megaphone and told the "experiences they have with racism," Bates said.

On the school's website, Principal Ray Aponte wrote that "students, their families and our staff have many different perspectives about the teenager's death, law enforcement's response and Ferguson as a whole. … We recognize that we don't know all the facts. We intend to listen to our students and ask open-ended questions so we can better understand their perspectives."

At Southwest High School, students staged a sit-in for much of the day. Student Isak Keller said in a text message that he and fellow students "began silence at 9:16" and then walked out at 1:46. "[That's] 4 ½ hours, for the time Mike Brown was left in the street."

Paul Walsh contributed to this report.

Libor Jany • 612-673-4064

Nicole Norfleet • 651-925-5032