http://www.livestream.com/occupyoakland

Update: Oakland Police estimate they’ve detained around 100 protesters as of 7:10 p.m.

OAKLAND — Oakland police deployed tear gas and smoke at about 500 Occupy Oakland marchers Saturday afternoon, arresting 19 protesters after they attempted to enter a vacant convention center, police said.

In the first major clash between protesters and police since November, three officers were injured, as protesters threw bottles, metal pipe, rocks, spray cans, “improvised explosive devices,” and lit flares, police said, in a large skirmish on the front steps of the Oakland Museum of California.

The marchers had announced plans to occupy a vacant building to create the movement’s headquarters, with plans for a two-day party. Police and city officials vowed to not allow it.