Italian authorities claimed a major victory Wednesday against a key money-laundering channel used by the 'Ndrangheta mafia, as they conducted a nationwide sweep on mob-controlled betting activities. Police issued 28 arrest warrants to mobsters who were already in jail, placed another 13 under house arrest and seized assets worth around 2 billion euros (2.2 billion dollars), including 1,500 betting shops, 82 gambling websites, 45 companies in Italy and 11 abroad. "Online betting is certainly the 'Ndrangheta preferred way to recycle profits from drug [trafficking]," dpa quoted Italy's top anti-Mafia prosecutor Franco Roberti as saying in a press conference in Reggio Calabria.