UPDATE #2: Four Denver Police officers were injured by a motorist suffering "medical issues" while they were escorting students from downtown Denver back to East High School—Denver Post:
The officers and the driver were transported to Denver Health. One officer in critical condition was taken into surgery, Police Chief Robert White said. Another officer had serious injuries. The two other officers were treated for "minor injuries," White said.
White added it is "not our best day."
Four mangled bicycles were seen on the north side of Colfax Avenue between High Street and Williams Street. A nurse on the scene was covered in blood, and a wide area was cordoned off by police.
UPDATE: FOX 31:
The Denver Post reported about 1,000 students took part in the march.
As they marched, students chanted “Hands up, don’t shoot” and “Justice for Michael,” according to several accounts on Twitter.
After reaching Civic Center Park, the crowd moved toward downtown along the 16th Street Mall. They mostly spread out and dispersed after that.
Around 11:30 a.m., the students regathered at Colfax and Broadway, where they held a 4 1/2-minute moment of silence, marking every hour Brown was in the street. The group then began a march back to the high school.
Just getting word of this, apparently a huge crowd of students from Denver's East High School have walked out of class this morning, shutting down Colfax Avenue near the Colorado state capitol in protest over the shooting of African-American teen Michael Brown in Ferguson, Missouri:
— Gena Ozols (@genaozols) December 3, 2014
— Justin Adams (@justinadams81) December 3, 2014
They were only expecting 30 people. Close to 1000 by my count.
— Jesse Aaron Paul (@JesseAPaul) December 3, 2014
We'll update with coverage once available–looks like a pretty big event.