The CBI has begun a probe into a 487 crore rupee scam related to over valuation of inferior quality of coal imported from Indonesia, which was passed on to NTPC and other power generation companies in collusion with officials. The action of the agency came on the basis of a Directorate of Revenue Intelligence investigation which had shown over invoicing in the imports between 2011-12 and 2014-15. <br/><br/>The agency's FIR is against promoter of Coastal Energy Private Limited, Channi and unidentified officials of NTPC, Metals and Minerals Trading Corporation, Aravali Power Company Private limited. CBI has booked them under the charges of criminal conspiracy cheating and provisions of the Prevention of Corruption Act. It is alleged that they entered into a criminal conspiracy to cheat the government by importing coal of Indonesian origin by fraudulently showing inferior quality coal as that of superior quality.<br/>