Tourists are stealing cobblestones, marble mile markers and bits of mosaic from ancient Rome and are being caught at customs trying to smuggle them home, airport police have disclosed.
Dozens of the square stones used by Romans 2,000 years ago to pave roads are ending up in passengers hand luggage.
Security staff screening bags at the Italian capital's main airports at Fiumicino and Ciampino have reported a surge in findings as x-ray scanners pick up the objects when luggage is screened and they in turn call police.
On Sunday, police in Rome put on display a vast collection of the cobblestones and artefacts that they have seized from passenger luggage in the first six months of this year.
The majority of those caught are "northern Europeans" and several British tourists have been among those caught red handed and left embarrassed in front of other passengers when items are pulled from their luggage.
Ancient Romans used volcanic stone to make the cobbles for the roads that led away from the city and they date back 2,000 years.
Police chief Antonio Del Greco said: "It's a particularly unusual theft and at the same time it's one that we are finding is on the increase and happening more and more often.
"Those primarily responsible are northern Europeans who have simply picked up a loose cobble stone or piece of mosaic they have found while wandering around Rome.
"They then put it in their luggage and take it home with them as a souvenir of their holiday â we have also found large milestones made from marble in suitcases that have been taken from the Appian Way."
Although the items have no real monetary value, Mr Del Greco said it was technically still theft and they are "taking away part of Rome's culture and heritage".
Mr Del Greco added that those caught were left "highly embarrassed" but were not arrested, instead they were cautioned and allowed to return home and their ancient souvenirs returned.
Umberto Broccoli, superintendent of culture for Rome city council, said: "I should warn all tourists that the city's rich heritage should not be touched. What these people do by stealing these items is show their ignorance.
"I can understand the legend and splendour that is Rome but that does not mean bits of it should be stolen by all means tourists should take as many pictures as they like but they should not help themselves to cobblestones or other items even if they appear to be discarded.
"If they want a souvenir of their visit then they should buy something from a shop."