New Delhi, April 16: The CBI on Monday said it has filed a charge-sheet against former Railway Minister Lalu Prasad and others in connection with its probe into alleged irregularities in the 2006 IRCTC hotels maintenance contract case. A Central Bureau of Investigation (CBI) official said that the agency had filed a case against Lalu Prasad, his wife and former Bihar Chief Minister Rabri Devi, his son and former Bihar Deputy Chief Minister Tejashwi Yadav and others. The case pertains to the period when Lalu Prasad was the Railway Minister. On April 10, the CBI had grilled Rabri Devi for hours in Patna in connection with the case. In October last year, the investigating agency had questioned Lalu Prasad and his younger son Tejashwi Yadav in the case at its Delhi headquarters.