Police suspect that the man might have mistaken the ambulance for his Audi under the influence of alcohol.
Narrating the sequence of events, the police said a businessman, in his thirties, visited the hospital in Thousand Lights area in Chennai early Sunday to drop his friend who had sustained some injuries.
After leaving him, he drove back in a Maruti Omni which was used as an ambulance by the hospital. The driver of the ambulance had left the keys in the vehicle, the police said.
The businessman realised his mistake when his family questioned him about his car after he reached home in suburban Palavakkam, about 15 km away from the hospital.
The man immediately asked his driver to take the ambulance back.
The driver apologised to the hospital authorities and police on behalf his owner and explained that the incident was a case of "mistaken identity."
The driver also compensated for a damaged rear-view mirror of the ambulance before driving away in the Audi.
Unsure if the businessman was drunk, the hospital decided to not lodge a police complaint.
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