Portuguese and European police say they have broken up a cell of an important Russian mafia group that allegedly laundered money through European football clubs.

The group identified EU football clubs in financial distress and infiltrated them with benefactors who brought much-needed cash, according to Europol, the European Union’s law enforcement agency.

Once they were in control, the mobsters allegedly laundered millions of euros through player transfers, TV rights deals and betting.

Portuguese and European police said they raided third division Portuguese club Uniao de Leiria and arrested three key members of the Russian gang. Three other Portuguese clubs’ premises were searched.

Europol said the operation helped identify serious crimes in Austria, Germany and the United Kingdom, though it gave no details.