Spanish police have arrested a man said to have smuggled himself in a case on to Barcelona airport coaches in order to burgle the luggage compartments.
An alleged accomplice was also arrested after the first man was found "doubled up almost like a contortionist" inside the case, police said.
Asked what he was doing, the suitcase man, who wore a head lamp, said he had been unable to pay the coach fare.
Police had been alerted after a string of thefts on the shuttle service.
The alleged burglar was also found with a sharp tool apparently used for opening zips and locks, as well as a small bag and a mobile phone.
Warm to the touch
Police believe the man was loaded on to coaches by his accomplice, who would then reclaim him after the 90-minute return trip to Barcelona's Girona airport.
"Once the trip began, he would get out of the suitcase, search for valuable objects and hide them in a smaller bag he carried with him," regional Catalan police were quoted as saying by AFP news agency.
But last Friday, Spain's el Periodico newspaper reports, a coach company employee noticed a man struggling to put a heavy suitcase in the hold of a coach and alerted the authorities.
Police officers knocked on the case and noticed that it was warm.
Inside, they found the alleged burglar, who was pouring with sweat. His alleged accomplice had already boarded the coach.
The two men, both Polish citizens, were arrested for the theft of a laptop and a GPS device, while police are seeking to trace other possible burglary victims.
El Periodico, which included a diagram of the alleged bus burglary scheme on its Spanish-language website, did not give details of the suitcase man's stature.