DENVER — Students from at least four Denver high schools joined in protests against police actions in Ferguson, Missouri, and New York City on Thursday.

They included students from Abraham Lincoln High School, who left class and walked about 6 miles to the state Capitol, snarling traffic along the way. Buses were sent to pick up the students after the protest.

Students from George Washington and Bruce Randolph high schools as well as Noel Community Arts School also left classes to protest.

The demonstrations came a day after hundreds of students at Denver’s East High School marched to the Capitol to protest the grand jury’s decision not to indict a police officer in the shooting death of Michael Brown in Ferguson. A police officer monitoring that protest was critically injured after being struck by a car in an apparent accident. Police said Thursday that Officer John Adsit had a “good night,” but he was expected to undergo more surgeries during the day.

During Thursday’s Abraham Lincoln protest, emergency vehicles drove slowly down streets as students walked on the sidewalk.

The students at the Capitol held a banner reading, “We Are Ferguson” and signs that said “Power In Unity.” They chanted, “Hands up, don’t shoot!” and “What do we want? Justice!”

Jose Romero, 18, was one of the students who organized the march. The grand jury decision to not charge a New York City police officer in the chokehold death of an unarmed black man inspired him to rally his classmates to demonstrate, he said.

“I was outraged by that,” Romero said of the New York case. He said he posted his plan on Facebook “encouraging every student to participate in a walkout for what’s just.”

Also in Denver, four people were arrested Wednesday night for obstructing traffic and interference during a protest of the grand jury’s decision not to indict a New York City police officer in the death of Eric Garner.

Police used Twitter to warn drivers to watch out for the protesters.

Montbello High School students joined protests Thursday in Denver. (Via Twitter, @RussellHaythorn)

Hundreds of students walk out of Denver Lincoln High School in Ferguson protest. They marched and arrived at the Capitol on Thursday, December 4, 2014. (Craig Walker, The Denver Post)

About 300 students walked out of class at Denver’s Abraham Lincoln High School on Thursday, rallying in support of protesters in Ferguson, Mo. (The Denver Post)