Italian police have arrested 54 suspected mobsters in Umbria, where investigators say the southern 'ndrangheta crime syndicate has infiltrated the solar panel industry and other "green economy" businesses.

Wednesday's crackdown appeared to confirm that the syndicate, lush with cocaine revenue, has increasingly spread out from its base in Calabria to invest elsewhere in apparently legitimate business sectors.

Gen. Mario Parente of the paramilitary Carabinieri police told reporters that Umbria, a central region of small towns and rolling countryside, largely had been seen as a "happy island" immune to organized crime, but that the current probe "shows it's not."

Officials praised local businesses for cooperating in the loansharking and extortion investigation, noting that elsewhere in Italy many businessmen preyed on by mobsters won't do that for fear of retaliation.