The raids follow the arrest of Ndrangheta chief Pasquale Condello

In dawn raids, heavily armed special forces seized a number of houses, cars, land and businesses in Calabria and the northern industrial region of L****ardi.

The areas are strongholds of feuding mafia clans under investigation for six murders in Germany last August.

Thirty people have been arrested since six Italian men were gunned down in the north-western city of Duisburg.

Several bank accounts were frozen as masked police carried out Tuesday's operation.

The raids came two weeks after Italian police arrested alleged Ndrangheta chief Pasquale Condello, 57, in Calabria.

Family ties

But while the seizure of $220m of assets might sound like a resounding success, it is small change compared to the group's profits.

The Ndrangheta has almost "exclusive" control over cocaine imports from Col****ia, with estimated annual sales of $50bn dollars.

Last week, a parliamentary report noted that its operations have now spread from Italy, to much of Europe, as well as the United States, Argentina and Australia.

The Ndrangheta has become a far bigger threat than the Cosa Nostra, and what sets this group apart from other crime syndicates is its structure.

It relies on close family ties, which means it is less vulnerable to turncoats.

It is so tightly organised that it is now one of the strongest, most dangerous mafia groups in the world.