Italian police Friday seized assets worth 350 million euros ($428 million) including a giant wind farm in a crackdown on the 'Ndrangheta mafia in the southern region of Calabria, investigators said.

The main suspect in the investigation is 55-year-old Pasquale Arena, the nephew of a notorious local mob clan leader and head of urban planning for the town council in Isola Capo Rizzuto, Colonel Fabio Canziani told AFP.

Arena is suspected of having had a wind farm built on behalf of the clan through shell companies based in Germany, San Marino and Switzerland.

The wind farm has 48 generators and is considered one of the biggest in Europe in surface area and output, investigators said in a statement.

Arena himself has not been arrested and was present at the raids. A total of 31 people including two German nationals are under investigation.