SAN DIEGO (AP) — A 57-year-old man has been charged with arson in one of 10 wildfires that swept the San Diego region this week.

Alberto Serrato pleaded not guilty Friday in connection with a 105-acre fire in suburban Oceanside — one of the smaller fires. The fire started Wednesday and is fully contained.

Tanya Sierra, a spokeswoman for the San Diego County district attorney’s office, says Serrato wasn’t seen igniting a fire but witnesses saw him adding dead brush onto smoldering bushes that flamed up. The spokeswoman says he has not been connected to any other fire.

The San Diego County sheriff’s website says Serrato was arrested Wednesday in Oceanside. He faces up to seven years in prison if convicted.

The DA’s office didn’t know if he has a lawyer who could comment.

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