The 38-year-old, who is an employee at Gian Piero Bakery in Astoria, Queens, had left the van idling as he was delivering bread to businesses on West 44th Street in Times Square around 5:30 a.m.
That's when police say another man stole the vehicle, drove it about a block, and crashed into scaffolding at the corner of West 45th Street and 7th Avenue.
The deliveryman suffered a broken leg and broken hand after he grabbed onto the van as it sped away.
The 15-year-old boy was in the van at the time, it's not clear if he was injured.
They were both taken to the hospital.
The 30-year-old suspect was arrested and was taken to Bellevue Hospital for a psychological evaluation.
Police say charges against him are pending.
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