The incident occurred around 3 p.m. on Nov. 22, on Meadows Road in Lafayette, New Jersey State Police said.
It was unclear if the key was left unattended in the van or if the teen was able to locate it elsewhere.
The teen was taken to Newton Medical Center for a psychiatric evaluation and treatment, then released to custody of group home administrators, NJSP officials said.
He was charged with operating a vehicle without the owner's permission, failure to report an accident, driving without a license and careless driving.
On Oct. 30, the same teen kicked and banged on the windows of a bus, then stood in the street, stopping it from driving away, The NJ Herald reports.
The incident sparked a meeting between school and town officials to discuss safety measures.
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