Protests in Cleveland over police shooting of Tamir Rice

Several hundred people marched down a Cleveland exit ramp and temporarily blocked rush-hour traffic on a busy freeway while protesting a police officer's fatal shooting of a 12-year-old boy who had brandished a realistic-looking replica gun.

Police diverted traffic on Tuesday but did not act against the protesters, who chanted phrases such as "Hands up, don't shoot" and "No justice, no peace" as they sat in a major intersection before marching past City Hall and onto a highway.

They were demonstrating after the death of Tamir Rice, who was shot on Saturday when police responded to an emergency call about a gun at a playground. Police later determined Tamir had an airsoft gun, which typically shoots plastic pellets.

The demonstration came as protesters across the US blasted a grand jury's decision in Ferguson, Missouri, not to indict a white police officer who killed an unarmed black 18-year-old.

Cleveland police Chief Calvin Williams was conferring with officers about the local protest but declined to comment.

The crowd - which included people of various races and college students - blocked the freeway for about an hour before returning to a downtown square and dispersing.