Baltimore police said some of the protesters that took to the streets to draw attention to the death of Freddie Gray on Saturday turned violent, breaking windows and throwing items at police.
Police cleared Freddie Gray protesters of an intersection near the
Baltimore Orioles game.
The number of what police called "agitators" dwindled downtown, as a line of officers pushed protesters away from the intersection they'd blocked for hours.
At least 12 people were arrested and two were injured in the mayhem, according to the Associated Press.
"We are doing our best to facilitate everyone's [sic] right to be heard," said the Baltimore Police on its Twitter account.
A video posted by a reporter for The Baltimore Sun showed a man smashing a trash can on the window of a police car. Others climbed on nearby parked cars.
Protesters had promised this would be their biggest march yet after near-daily demonstrations this week over the death of Freddie Gray. Thousands of people took to the street for demonstrations that were peaceful for much of the day.
The protest came a day after police said Gray did not receive medical attention early enough after being taken into custody and that Gray was not buckled into a seat when he was transported in a police van after he was arrested April 12.