Paramedics were putting an unoccupied stretcher into an empty ambulance at Norwegian-American Hospital when the man got in and took off, the Chicago Tribune reported.
He crashed the ambulance a mile and a half away, hitting several vehicles on the way, Chicago Police News Affairs Officer Amina Greer said.
The man suffered minor injuries and was transported back to Norwegian-American Hospital in another ambulance.
Charges are pending, the newspaper said.
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