Mafia launders £2.4bn into Rome's Restaurants (Reuters picture)

Pizzerias have long been the favourite haunts of mafia bosses in Rome.

But instead of dining in them, gangsters are buying up the capital's hotels, restaurants and bars to launder £2.4bn of dirty money, according to the Sunday Times.

Anti-mafia investigators say Mafiosi are targeting property owners who are being forced to sell because of the poor economic climate.

Most recently, police seized the four-star Grand Hotel del Gianicolo - a former monastery - from property magnate Giuseppe Mattiani and his son Pasquale, who are linked to the 'Ndrangheta mafia in Calabria, southern Italy. Mattiani allegedly paid cash for the hotel.

A police officer said: "This goes to show how far 'Ndrangheta money has penetrated the Italian capital. They are quite bold about where they will launder their money."

Antico Caffe Chigi - an elegant bar near the prime minister and the lower house of parliament in the city - has also been seized for having mafia links.

Over the last two-and-a-half years, Italy's finance police have seized £1.2bn of assets from organised crime gangs and have asked for permission to seize another £1.2bn of assets.

Dirty money is said to be turning Rome into a money-laundering capital for the Calabrian mafia, who control the European cocaine trade, and the Camorra mafia.

Hotels, bars and restauarants make up half of the 160 businesses seized in Rome. But they pale into insignificance in comparison to the mob's profits .

According to the interior ministry, the 'Ndrangheta's profits from cocaine come to €40bn (£34bn) a year - 3% of Italy's GDP.

The Calabrian gangsters' first high-profile purchase was the Café de Paris on the Via Veneto (the road that symbolises Rome's Dolce Vita). It reopened two years after being seized.

In its heyday the bar attracted Sophia Loren, Ava Gardner and Frank Sinatra. Today it offers red wine, olive oil and pasta produced on land seized from the mafia.