Ferguson demonstrators in Washington, D.C., briefly shut down a portion of Interstate 395 on Sunday afternoon.
According to The Washington Post, a human chain formed across the highway shortly before 1 p.m., blocking traffic in both directions. Traffic was moving regularly by 1:40 p.m., police told the Post.
Police told NBC News that about three dozen demonstrators blocked the road and eight were willingly taken into custody.
There were also protests in St. Louis on Sunday, where demonstrators marched to the Edward Jones Dome after the St. Louis Rams football game.
The protests were the latest among many that have occurred nationwide since Monday, when the St. Louis county prosecutor announced the grand jury's decision not to indict Darren Wilson, a white police officer who killed Michael Brown, an 18-year-old black teenager, in August.