The Central Bureau of Investigation on Tuesday arrested Vipul Chitalia, vice president of banking operations at the Gitanjali Group of Companies, in connection with the alleged scam involving the Punjab National Bank. After investigators called him the mastermind of the Rs 12,703-crore fraud, a special CBI court remanded him in the agency’s custody till March 17.

Earlier in the day, the CBI had detained Chitalia at the Mumbai airport and taken him to its office in Bandra-Kurla Complex for questioning.

Jewellers Nirav Modi and his uncle Mehul Choksi, who is a promoter of Gitanjali Gems, are accused of defrauding the Punjab National Bank of Rs 12,703 crore. A few officials of the bank are alleged to have fraudulently issued Letters of Undertaking – essentially letters of credit that tell others banks that it will meet a customer’s liabilities – to Modi’s companies. The CBI had arrested a number of Punjab National Bank executives for their alleged involvement in the scam.