They went to the baggage conveyor belt – and found a tourist curled up in a drunken sleep.
The 36-year-old man had travelled for 15 minutes after getting on the belt next to an unmanned check-in desk.
Police are said to have had difficulty waking the unnamed Norwegian, who was still sleeping in the foetal position, when they responded to the security breach at Fiumicino airport in Rome.
He was taken to hospital to be checked over because of concerns he may have been injured by exposure to the powerful X-rays. He is now being investigated for causing alarm.
An airport official said: ‘It’s impossible to avoid a situation like this if there’s no employee at the check-in desk.’ The man reportedly arrived at Terminal 3 with a rucksack and a can of beer in his hand to check in for a flight to Oslo.
He appeared to have been drinking heavily.
Denying the unscheduled trip had exposed lax security, another official said: ‘The Norwegian could have carried on going round the main belt, but he could never have ended up in sensitive areas of the airport.’