The practice of illegally issuing Letters of Understanding (LoUs) and Foreign Letter of Credits (FLCs) and then rolling them over to favour Nirav Modi and Mehul Choksi groups started in 2008 and continued till these were discovered in January this year, according to CBI officials.

The illicit activities resulting in fraud of Rs 11,300 crore occurred under the nose of top Punjab National Bank officials but they claimed to be unaware of the scam.