Westchester County police say a 17-year-old boy with autism who went missing Thursday has been found safe.

School officials say Gene Warren wandered off while participating in an educational program at the county office building in White Plains. A chaperone noticed that he had gone missing at around 11:20 a.m.

Investigators say they believed the teen may have run away because he has a history of hopping on buses and trains. County police searched in Yonkers, White Plains and Brooklyn. They say Warren had a history of traveling to Brooklyn in the past.

He was found at his grandmother's house in the Bronx. School officials say Warren was found with help from police, school staff and his family.

Officers took Warren to Jacobi Medical Center for evaluation.

The teen lives at the Leake & Watts residential treatment center and school in Yonkers.

It is still unclear who was responsible for keeping an eye on the teen when he wandered off and how he managed to slip away. Calls seeking comment from county police have not been returned.