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Occupy Oakland protests - Wednesday 26 October
Police used tear gas to disperse an Occupy Oakland march overnight, with reports of injuries from rubber bullets or baton rounds.
Police have said they did not use flash bang grenades to clear demonstrators, but some sort of explosive is clearly thrown into the crowd in the footage.
YouTube user PlanetEarthAwakens1 identifies the figure on the floor as Scott Olsen, a Veterans for Peace member.
Video footage shows Olsen lying prone on the ground in front of police lines. A crowd gathers in an apparent bid to help him, but then scatters when a police officer throws an explosive device into their midst.