MONTEBELLO (CBSLA.com)   —  Police in Montebello are asking the public to be on the lookout for a missing teen.

Officials said Jose Arellano ran away Friday evening.

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Arellano is described as a high-functioning person with autism.

Hwas last seen at home Friday night. His mom woke up Saturday morning and discovered him gone.

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He left a note in which he indicated he was unhappy with his last interaction with his therapist.

Arellano likes to frequent libraries and parks in the city of Montebello.

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If you have seen him, please contact the police (323) 887-1200