The men arrested are suspected of having sold forged paintings for more than €2 million to customers in Germany and Spain between 2011 and 2013. Yet they were said to have been active for much longer, selling forged paintings around the world for huge sums.
The federal criminal police office or BKA said in a statement that two men, aged 41 and 67, were arrested after a large number of flats, offices, warehouses and galleries were raided in the cities of Wiesbaden, Mainz, Stuttgart, Munich, Hamburg and Cologne.
More than 1,000 objects, including suspected forged paintings and sale documentation, were seized.
Searches were also carried out in Switzerland and Israel.
The men are believed to be the ringleaders of a gang of six counterfeiters who specialize in forging paintings by Russian avant-garde artists including Wassily Kandinsky and Alexej Jawlensky.
The suspected counterfeiters are of Russian, Israeli and German-Tunisian nationality who are believed to have sold more than 400 forged paintings for sums ranging from the thousands to millions since 2005.