CLEARLAKE OAKS, Calif. (AP) — Authorities are trying to determine why a gunman shot up homes and stores in a small Northern California town, killing two people and injuring two others.

Sixty-one-year-old Alan Ashmore was arrested Monday at a roadblock after he allegedly opened fire at homes, a car, two gas stations and a winery in his hometown of Clearlake Oaks, northwest of Sacramento.

One man was killed in a home, another in a car, and a woman and a California Highway Patrol officer were shot. Authorities say the woman is expected to live, and the officer's body armor kept him from serious harm.

Lake County Sheriff Brian Martin says it's unclear whether the gunman targeted people, fired randomly or did both.

He tells San Francisco's KPIX-TV that Ashmore had spent time in prison and had been arrested several times locally.

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