Italian prosecutors have obtained records and photographs that they claim show the head of an international smuggling syndicate that was behind the illegal excavation of antiquities in Italy had dealt with a Japanese antique art dealer, it has been learned.

The Italian prosecutors suspected that a number of antiquities housed at some museums or owned by individual collectors in Japan might have been illegally dug up at Italian archaeological sites.

The prosecutors named Gianfranco Becchina, an Italian art dealer, as the head of the antiquities smuggling syndicate.

One of the prosecutors, who spoke on condition of anonymity, said Becchina is from Sicily and is suspected to have links with the Mafia.

The prosecution searched a warehouse owned by Becchina in Basel, Switzerland, in 2002 and 2005 on suspicion he smuggled illegal items. The searches found 10,000 photographs of items believed to have been illegally excavated or stolen, and about 200 bundles of receipts, according to prosecution sources.

One of the receipts, which detailed a transaction made in April 1991, bore the names of Becchina and a Japanese antique dealer, leading the prosecutors to believe the two engaged in trade.

From about 1970 to the end of the '90s, when sales of antiquities were brisk worldwide, looting was rampant at ancient Roman ruins and elsewhere in Italy.

The prosecutors believe Becchina had been buying items from looters and selling them to dealers around the world.

Illegally excavated items are known to have been auctioned in London and New York, and some have been purchased by museums and individuals in various countries, including Japan, they said.

The Japanese antique dealer in question is based in London and trades extensively in Europe.

The Italian prosecution sources said they suspect the Japanese dealer sold items to the Miho Museum in Koka, Shiga Prefecture, which was earlier cited by Italian prosecutors as having contraband Italian antiquities in its collection.

The Japanese dealer, who spoke on condition of anonymity over the phone with The Yomiuri Shimbun, said he has had business relations with Becchina since 1989.

The Japanese dealer denied he knew that the items offered by Becchina might have been illegally excavated, noting, "I trusted Becchina completely when I bought items from him."

He declined to go into the specifics of his relationship with the Miho Museum, which opened in 1997, but said he "bought some pieces on behalf of several Japanese art collectors, who assisted the Miho Museum with its collection." The dealer declined to say whether those pieces included ones sold by Becchina.

The Italian prosecution sources, however, said some Polaroid photos seized in the raids depicted items the Japanese dealer bought for Miho Museum.

Another Italian antiquities dealer, Giacomo Medici, who was a business rival of Becchina, was arrested in January 1997 and sentenced by a district court in Italy to 10 years in prison for smuggling ill-gotten artworks.

During investigations into Medici's smuggling charges, photos showing items that were displayed at the Miho Museum also were found, the sources said.