In an elaborate scam that could have come straight from the plot of the film The Thomas Crown Affair, investigators believe that having identified a target, [Count Cristiano] Barozzi would take a digital photo of the painting, produce a copy and replace the original with the fake.

The thefts are alleged to have continued for a decade, during which time none of the owners realised they had been robbed. According to the police, Barozzi's keen eye was most attracted to artworks hanging in poorly lit areas, where the copies would not be detected.

The aristocrat's gang members are alleged to be two Sri Lankan butlers who worked for the victims, Claudio Mella, a consultant with the regional monuments and fine arts agency, who allegedly identified the paintings and then advised Barozzi on selling them, and Claudio Celadin, an expert in digital photography.

Over a few months last year, five thefts netted the thieves more than E1 million ($1.3m). The stolen artworks were predominantly painted by the schools of Old Masters rather than by the masters themselves, because these are easier to sell on the black market.