The CBI today filed a chargesheet against suspected mining mafia member and main accused Manoj Gurjar in murder case of Madhya Pradesh IPS officer Narendra Kumar Singh in Indore.Gurjar allegedly mowed down 32-year-old Singh, who was posted as Sub Divisional Officer of Police (SDOP) at Barmore town in Morena district, on March 8 when he tried to intercept a tractor-trolley laden with illegally mined stones.Gurjar has been charged under section 304 and 353 of Indian Penal Code and Motor Vehicle Act.CBI prosecutor A H Khan said it was not an intentional murder and was non-political. The maximum punishment in the case is 10 years or life imprisonment.The next hearing in the case will be on June 11.