NEW DELHI: Bank fraud fugitive Mehul Choksi has surrendered his Indian passport to the High Commission in Guyana, official sources said on Monday.Indian citizens are expected to surrender their passports when they acquire a foreign nationality.India continues to pursue Choksi's return with the government of Antigua through diplomatic and legal channels, the sources said.In August last year, India gave Antigua a request for Choksi's extradition. A team from India was also sent to Antigua to pursue the request.Choksi and his nephew Nirav Modi, in connivance with certain bank officials, allegedly cheated Punjab National Bank (PNB) of about Rs 14,000 crore through issuance of fraudulent letters of undertaking. A Mumbai branch of PNB had fraudulently issued LoUs for the group of companies belonging to Nirav Modi since March 2011.The total number of LoUs issued to the companies of Nirav Modi, his relatives and the Nirav Modi Group are 1,213, and to Mehul Choksi, his relatives and the Gitanjali Group are 377.Choksi and Nirav Modi fled the country in January last year before the country's biggest banking scam was unearthed.The CBI has already filed chargesheet in this case. The chargesheet has mentioned names of many employees and top management, including former managing directors and executive directors of the bank.The government has issued non-bailable warrants against both Choksi and Nirav Modi and Interpol red notices are out too.