Police in Italy have arrested 20 people and seized some 17 seaside resorts along the southern coast in a crackdown on organized crime clans suspected of laundering money through the tourist industry.

Italian prosecutor Nicola Gratteri told reporters in Reggio Calabria that two `ndrangheta crime syndicate clans are believed to have invested illicit revenue in the resorts.

Authorities said those arrested Tuesday include two Spanish businessmen with dealings with the `ndrangheta, which is based in southern Calabria.

Prosecutors say the probe indicates that a Belfast-based developer was also involved in the alleged laundering scheme, but it was not immediately clear if the developer was arrested.

Prosecutors were not immediately available for comment. The seized tourist resorts and vacation homes were valued by authorities at some (EURO)450 million ($600 million).