MUMBAI, Dec. 6 -- Three former senior government officials, including a former chairman of the Airports Authority of India (AAI), and three private firms, including two based in Mumbai, have been charged in an alleged corruption case relating to irregularities in contracts for food and beverages (F&B) for the Chennai and Kolkata airports in 2012-2013. The case, registered by the Central Bureau of Investigation (CBI) on Tuesday, is based on a complaint from a CBI inspector and the findings of a preliminary inquiry, which probed allegations that AAI officials had manipulated the tender process and illegally modified the terms of commercial contracts in 2012-13. The contracts in question refer to developing, operating and maintaining all F&B outlets at the two airports, awarded by the AAI to private companies. The CBI's First Information Report (FIR) names as accused then AAI chairperson, VP Agarwal, then AAI member (finance) S Suresh and then AAI official R Bhandari. The FIR also names three firms, including Travel Food Services Chennai Pvt Ltd, Mumbai; Travel Food Services Kolkata Pvt Ltd, Mumbai; and Devyani International Ltd, New Delhi. The accused have been charged under the Indian penal Code and Prevention of Corruption Act, for criminal conspiracy, cheating and criminal misconduct by public servants. The AAI had adopted a two-stage process to select bidders to develop, operate and maintain F&B outlets at the Chennai and Kolkata. In the first stage, applicants were required to furnish certain information. Thereafter, only applicants who pre-qualified and shortlisted by AAI were eligible for participation. After selecting technically qualified bidders, AAI was to invite financial bids. The FIR alleged that the terms and conditions of RFQ were allegedly changed, to provide undue financial favours to the successful bidders....