Employees of Deutsche Bank, Germany's largest bank, have come under suspicion of involvement in a scheme to avoid taxation on emissions trading, dpa quoted state prosecutors as saying today. In nationwide raids on Wednesday, which included the headquarters of Deutsche Bank in Frankfurt, the country's financial capital, and offices of energy giant RWE, some 230 premises were searched. The investigation concerns some 50 companies and over 150 suspects, who are thought to have bought carbon credits from abroad and resold them through interconnected companies in Germany without declaring or paying the appropriate sales tax, prosecutors said. A spokesman for Deutsche Bank confirmed on Thursday that seven of its employees were among those under suspicion. Three arrests have so far been made. Frankfurt prosecutor Guenter Wittig gave no further details regarding the investigations, but said that examination of confiscated mobile phones, laptops and hard-drives could take months. The last link in the chain of companies in the so-called carousel fraud is thought to have resold the carbon certificates abroad, entitling them to sales tax reimbursements from the government. A spokesman for the bank was quoted in the Frankfurter Allgemeine newspaper saying "we are supporting the state prosecutors with their investigation." The amount claimed to have been lost to the tax authorities was some 180 million euros (237 million dollars).