Police in four countries made scores of arrests on Wednesday, after busting an international criminal gang who stole artifacts from Sicilian archaeological sites, the EU's police agency said.

The predawn raids on over 40 houses were the culmination of a four-year investigation led by Italy's Carabinieri Art Squad, Europol said.

The group "illegally exported" many of the stolen artifacts to Germany, where they were granted fake certificates of origin and sold by auction houses in Munich, Italian police said.

Read more: The most spectacular art robberies in history

Some of the 25,000 objects recovered included ancient coins, statues and pottery, as well as fake artifacts that were estimated to be worth over €40 million ($46.5 million). Police also seized about 1,500 tools used by the gang to illegally excavate archaeological sites in central Sicily, where Greek and Roman artifacts can be found.

The ancient temple of Zeus located in Sicily used to be one of the largest of its kind in the Mediterranean region

Across several countries

Twenty-three people have been arrested in relation to the gang, with eight in custody, seven under house arrest in Italy, and three subject to European arrest warrants in Germany, Spain and Britain.

A 61-year-old Italian was arrested in Ehingen, in the southwestern German state of Baden-Württemberg, and €30,000 in cash was seized from his home.

Read more: How Paris' 100-million-euro art heist happened

William Veres, a British art dealer, was served an international arrest warrant and was detained in London. Another Italian was arrested in Barcelona.

The group's alleged leader is a 76-year-old man known as "Zu Gino" (Uncle Gino), who worked out of the Sicilian town of Riesi.

Police are also investigating two Munich auction houses.

Another five suspects were not detained, but have been ordered to report regularly to police, the art heritage squad said.

Most expensive artworks sold at auction Monet's 'Meules': $110.7 million The French painter Claude Monet created multiple landscape series that depict the same subject in different types of light and seasons, showing off his ability to capture atmosphere. The painting "Meules" (1890), from his "Haystacks" series, fetched $110.7 million (€98 million) at a Soethby's auction — the record for a Monet and the first impressionist painting to cross the $100-million threshold.

Most expensive artworks sold at auction Da Vinci's 'Salvator Mundi': $450.3 million Created around 1500, this painting of Christ attributed to Leonardo da Vinci is one of the master's 20 still existing paintings. In 1958 "Salvator Mundi" was sold for just $60 because it was thought to be a copy. But it fetched more than four times Christie's pre-sale estimate on November 15, 2017, when it was sold for over $450 million (€382 million) — setting a world record for auctioned art.

Most expensive artworks sold at auction Picasso's 'Women of Algiers': $179.4 million From 1954-55, Pablo Picasso did a series of 15 paintings inspired by Delacroix's "Les Femmes d'Alger," with versions named "A" through "O." He started them after the death of Henry Matisse, as a tribute to his friend and artistic rival. "Version O" broke the world record for an auction sale, selling for $179.4 million (167.1 million euros) at Christie's in May 2015.

Most expensive artworks sold at auction Modigliani's 'Reclining Nude': $170.4 million At a Christie's auction held in November 2015, seven potential buyers spent nine frantic minutes bidding on this painting. It was finally snapped by a telephone bidder from China. The nude, painted in 1917-18, provoked a scandal at its first exhibition in Paris. The police shut down the art show after a crowd gathered outside the window.

Most expensive artworks sold at auction Modigliani's 'Nude lying on her left side': $157.2 million Modigliani's work "Nu couché (sur le côté gauche)" caused such a controversy when it was first shown in Paris in 1917 that the police had to close the exhibition. The Italian artist's oil painting became the most expensive artwork to have been sold at New York auction house Sotheby's in May 2018.

Most expensive artworks sold at auction Klimt's 'The Woman in Gold': $135 million This 1907 painting by Gustav Klimt is considered one of the most elaborate and representative of his "golden phase." In 2006, it was sold through a private sale brokered by Christie's for a record sum for a painting, $135 million. That same year, Jackson Pollock's classic drip painting "No. 5 1948" broke that record, obtaining $140 million through another private sale.

Most expensive artworks sold at auction Van Gogh's 'Portrait of Dr. Gachet': $149.7 million Van Gogh allegedly said of the homeopathic doctor Dr. Gachet, whom he painted here in 1890, that "he was sicker than I am." The plant is a foxglove, which is used to make the drug digitalis. In 1990, the work was auctioned off to Ryoei Saito, Japan's second-largest paper manufacturer, for $82.5 million, making it the world's priciest painting at the time (the price above has been adjusted).

Most expensive artworks sold at auction Bacon's 'Three Studies of Lucian Freud': $142.4 million This 1969 triptych documents Francis Bacon's friendship and rivalry with fellow painter Lucian Freud. At the time it was sold, in November 2013, it obtained the highest price for a work of art at an auction, until Picasso - and now Modigliani - surpassed that record in 2015.

Most expensive artworks sold at auction Renoir's 'Dance at Moulin de la Galette': $141.7 million This 1876 work by Impressionist master Renoir depicts a dance venue for high society on the outskirts of Paris, the Moulin de la Galette. One of Renoir's most famous works, it exudes the joie de vivre that is characteristic of his style. In 1990, the work was purchased for $78.1 million (adjusted price above) by Japanese buyer Ryoei Saito, along with van Gogh's "Portrait of Dr. Gachet."

Most expensive artworks sold at auction Picasso's 'Boy with a Pipe': $130.7 million This portrait of an adolescent holding a pipe and wearing a garland of flowers in his hair was created during the Spanish master's "Rose Period" in 1905. Just a little under a century later, the painting fetched an impressive sum of $104.2 million at a Sotheby's auction in 2004 (price adjusted above).

Most expensive artworks sold at auction Munch's 'The Scream': $119.9 million This agonizing character painted by Edvard Munch is one of the most iconic paintings in the world. The Expressionist artist had actually made four versions of it: Three are in Norwegian museums, and the fourth one was sold for the screeching price of $119.9 million in May 2012 at Sotheby's, which would be adjusted to $130.7 million today.

Most expensive artworks sold at auction Picasso's 'Young Girl with a Flower Basket': $115 million Picasso is well represented among the highest earning painters. His 1905 masterpiece "Fillette a la corbeille fleurie" ("Young Girl with a Flower Basket") was sold – along with two other Rose Period paintings – by the artist himself to writer Gertrude Stein in a sale that helped launch his career. The work, which was later part of David and Peggy Rockefeller's collection, sold for $115 million.

Most expensive artworks sold at auction Picasso's 'Nude, Green Leaves and Bust': $106.5 million Inspired by his mistress Marie-Thérèse Walther, Picasso created this painting in a single day in 1932. If you add the eight minutes and six seconds it took for the auction record bid at Christie's in May 2010, it still appears to be well-invested time. Its price could be adjusted to $115.7 million today. Author: Elizabeth Grenier, Kate Müser



rs, law/kms (AP, AFP, dpa)