More than 100 art treasures including Dali's "Romeo and Juliet" and De Chirico's "Mannequin" were confiscated from Gioacchino Campolo, known as the "slot machine king", when he was arrested in 2009.

The art works lay in a bank vault for three years until the culture ministry, anti-Mafia prosecutors and local authorities agreed to stage the show, entitled "Art returns to art", in a Reggio Calabria museum that has been closed for renovation for the past four years, The Telegraph said.

Italian authorities said Campolo amassed a fortune worth more than 400 million euros (£350million) though his vast gambling operations, video poker and extortion and had an international property empire with homes in Paris, Rome, Milan and the upscale Sicilian resort town of Taormina.

According to anti-Mafia prosecutors Campolo is closely linked to the De Stefano family, one of the most powerful clans in the Calabrian Mafia, the 'Ndrangheta. He has now been convicted and sentenced to 16 years in prison for various crimes. He appeared to have an extraordinary weakness for art and was unable to resist the purchase of a new masterpiece for his luxury homes.

Among the paintings on show are 15 artworks that span the 16th and 19th centuries but there are also many works by leading Italian artists from the 20th century including Lucio Fontana, Luigi Veronese and two works by Antonio Ligabue.