Cologne police said witnesses called authorities around 7 p.m. Saturday to report a man was trapped inside a Porsche Cayenne sport utility vehicle, TheLocal.de reported Monday.
"Eyewitnesses reported that the man kicked the vehicle's door in panic ... but without success," police said in a statement.
Police said the 50-year-old man allegedly broke into the vehicle in an attempt to steal valuables, but was trapped when the central locking system activated.
Police said the owner of the vehicle arrived and unlocked the doors just as firefighters were preparing to free the suspect.
The man was arrested on suspicion of theft from a vehicle, police said.