The CBI on Thursday raided three premises in Noida and Lucknow in connection with a disproportionate assets case against former Uttar Pradesh Chief Secretary Akhand Pratap Singh. A large number of incriminating documents relating to properties in Delhi and Lucknow have been recovered and a contractor with Noida Authority, K M Khandelwal, has been arrested by the CBI, said sources. The CBI has also found some documents reportedly belonging to B P Khandelwal, former Chairman of CBSE, of a “benami” property acquired by him. The documents in CBI’s possession point to more assets in the name of the former Chief Secretary than what the agency had detected so far, sources said. Some documents pertaining to forged wills created by the accused official were also found from the premises of the contractor.