An art teacher at a charter school in Livermore, California, was allegedly found performing a sexual act in a car in unincorporated San Leandro and trying to attract the attention of passing trick or treaters on Halloween night, the Alameda County Sheriff's Office said Saturday.

The Sheriff's Office was contacted around 10:30 p.m. on Oct. 31 regarding the man, who was seen disturbing passing children at Mateo Street and Green Court, Sgt. J.D. Nelson said.

Deputies found Carlos Tellez sitting in his gold 1998 Mazda Protege with his pants unzipped and pulled down to mid-thigh and his shirt pulled up to mid-chest, Nelson said.

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He had been placed under citizen's arrest by a passer-by, and was detained without incident. Tellez, an art teacher for the Livermore Valley Charter Preparatory in the city of Livermore, told deputies he was trying to relax after a stressful day of teaching, Nelson said.

Investigators are looking for other possible witnesses or victims.

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