BERKELEY, Calif. (AP) - Three officers and a technician were hurt and six people arrested in Northern California when a protest over police killings turned violent.

The Oakland Tribune reported Sunday (http://tinyurl.com/qay5oem ) that police fired rubber bullets and used smoke and flares during a night-long protest in Berkeley that grew increasingly violent and unruly. Protesters smashed windows and threw rocks and bricks at police, who responded with tear gas. Five adults and one juvenile were arrested. Berkeley police didn't say if any protesters were hurt.

All the officers and the technician are expected to recover. The most serious injury was a dislocated shoulder, Berkeley police said.

Saturday night's demonstration against police killings of unarmed black men in Missouri and New York began peacefully, the latest of several in the Bay Area in recent days.