Protesters clash with police in Berkeley, California, over verdict in New York chokehold case

Protesters in northern California hurled objects at police, who responded by firing gas for a second consecutive night, as demonstrations continued over the death of a black man after he was put in a chokehold by a police officer in New York.

A crowd of about 750 demonstrators swarmed freeway overpasses at two locations in Berkeley, near San Francisco, prompting police to move in to clear the roadways and arrest several people on Sunday night.

The California Highway Patrol's Golden Gate division said on its Twitter feed that gas was fired after some demonstrators began hurling objects it described as unspecified "explosives", and arrests had been made, but exact numbers were not available.

Some demonstrators said on Twitter that police had fired rubber bullets, but this could not be confirmed.

West Coast cities had braced for trouble after clashes in nearby Berkeley and Seattle, Washington on Saturday. Protesters in New York and other cities have staged demonstrations every day since a grand jury's decision on Wednesday not to bring criminal charges against the white police officer whose chokehold contributed to the man's death in New York in July.

Saturday's looting and rock-throwing on the West Coast contrasted with the mostly peaceful demonstrations that have taken place elsewhere. New York was quieter over the weekend. Earlier on Sunday evening hundreds of protesters began marching down a main thoroughfare in Berkeley after massing on the campus of the University of California.

Officer Jenn Coats of the Berkeley Police Department said the crowd, estimated at 500 to 600, was peaceful.

On Saturday evening, what had begun as a peaceful march ended in an extended confrontation between demonstrators and police, resulting in six arrests, damage to local businesses and a minor injury to a police officer.

In downtown Seattle, about 200 people gathered on Sunday evening, a day after a demonstration drew more than 1,000 protesters, with some throwing rocks and attacking police in clashes that resulted in seven arrests.