Kolkata, Sep 27 : Even after being grilled for almost 12 hours by the Enforcement Directorate (ED) in connection with its probe into the multi-crore West Bengal School Service Commission (WBSSC) recruitment irregularities scam, former Minister Partha Chatterjee's son-in-law appeared clueless over a huge cash investment involving an international school in Pingla, West Midnapore district. Kalyanmoy Bhattacharya left the central agency's office in Salt Lake at around 2.30 a.m. on Tuesday following the lengthy questioning. Bhattacharya is the chairman of the BCM International School, named after Partha Chatterjee's late wife Babli. The premises are spread over 45 acres of land and have all the amenities of an international category school. ED sources said that the agency sleuths have come across documents related to expenditures made in cash worth around Rs 15 crore for setting up the school at different phases, like purchases of lands as well as payments to different contractors. The sleuths reportedly questioned Bhattacharya on each of these cash payments after placing the related documents in front of him. However, the sources said, Bhattacharya denied having any knowledge and at times even appeared clueless on certain expenditures. The probe agency believe that a portion of the scam proceeds were routed towards expenses for setting up the school. The ED sources said that much of this information and documents about the expenditures made were provided to their sleuths by the caretaker of the said school, Krishna Chandra Adhikari, a local resident of Pingla and also Bhattacharya's uncle. They said that Bhattacharya will be summoned again for questioning on three companies -- Improline Constructions Pvt Ltd, HRI Wealth Creation Realtors Pvt Ltd, and Acrisius Consulting Pvt Ltd. As per records of the Registrar of Companies under the Union Ministry of Commerce, while Bhattacharya is the Managing Director in Acrisius Consulting, in the remaining two companies, he is an ordinary Director. In HRI Wealth Creation Realtors and Improline Constructions, the second Director is Krishna Chandra Adhikari. Bhattacharya, who currently stays in the US with his wife and Chatterjee's daughter, Sohini, was summoned twice to come to Kolkata for questioning. However, he ducked both the summons then. He arrived in Kolkata on September 24 and immigration officials at the Netaji Subhash Chandra Bose International Airport alerted the ED. The ED officials immediately contacted him and asked him to be present at its Salt Lake office by Monday afternoon, to which he complied. /IANS