The Central Bureau of Investigation (CBI) on Wednesday registered a disproportionate assets case against former telecom minister A. Raja and 16 others."It is alleged that he (Raja) and other accused persons have amassed assets disproportionate to their known sources of income. Searches are being carried out at 20 places in Delhi, Chennai, Perambalur, Tiruchirappalli and Coimbatore," said a CBI official.On April 15, the CBI commenced the final argument in the case alleging that Raja misled then prime minister Manmohan Singh on policy matters related to 2G spectrum allocation.According to the CBI, Raja was biased in allocating 2G mobile airwaves and operating licences to telecom firms, causing a huge loss to the state exchequer.The court framed charges on October 22, 2011, against 14 accused and three companies under various provisions of the Indian Penal Code and the Prevention of Corruption Act.All the accused, including Raja, are out on bail.