Police from four countries have seized some 25,000 Greek and Roman archaeological items worth over €40 million in raids, cracking down on illegal trafficking in cultural goods.
The European Law Enforcement Agency said 23 suspects were detained.
The investigation, which began four years ago, revealed that the organised crime group behind the illegal excavation and trafficking of cultural goods was very well organised, operating from several EU member states.
The probe was initiated by the units specialised in the trafficking of cultural goods of the Italian Carabinieri and supported by its counterparts at the Spanish Guardia Civil, the British Metropolitan Police and the German LKA of Baden-Württemberg.
In Italy, the raids were focused on the regions of Sicily, Calabria, Piedmont and Apulia, in what is considered one of the biggest crackdowns in such crimes in Italian history.
Prosecutors believe the items were illegally excavated in Sicily, under commission by a London art dealer.
A spokeswoman for the UK's Metropolitan Police said that after acting on a European arrest warrant, officers had detained a 64-year-old man in the Greater London area and recovered three relics believed to be of Roman origin.
In the Sicilian Caltanissetta area, “which is rich in archaeological sites from the Greek and Roman epochs, local members of the organised crime group illegally excavated artefacts,” Europol said.
The items were then smuggled out of Italy, “equipped with false provenances and sold via German auction houses".
The criminal gang, which was said to be aided by "facilitators" in Barcelona and London, was described by the European police force as "very well organised".
Police also seized 1,500 tools, including metal detectors, in the early morning raids.
Major Luigi Mancuso of the Carabinieri paramilitary art squad in Palermo, Italy, said Wednesday that investigators allege the digs were commissioned by a London art dealer, William Veres, 64, who was served with an international warrant.
Europol said, “International cooperation is key to the success of such investigations in the field of trafficking of cultural goods, in which artefacts are moved through several EU countries and levels before they are brought to the legal market.”
The case is considered to be one of the largest of its kind involving the illegal removal of artefacts from archaeological sites in Italy.