The Punjab National Bank told police officials that it has uncovered additional exposure of about Rs 942 crore in connection with the massive alleged fraud it is at the centre of, Reuters reported on Tuesday. This disclosure takes the total value of the alleged fraud to Rs 13,645 crore.

In a court filing on Tuesday, the bank said the Gitanjali Group of Companies, controlled by jeweller Mehul Choksi, allegedly defrauded it of Rs 7,080 crore. Earlier, the Punjab National Bank had said that the group’s fraud amounted to Rs 6,138 crore.

An unidentified lawyer for Choksi told Reuters that he was unaware of the new allegations, and refused to comment.

On March 6, the Central Bureau of Investigation had arrested Vipul Chitalia, vice president of banking operations at the Gitanjali Group of Companies, in connection with the scam.

On March 8, the CBI filed a case against billionaire jeweller Nirav Modi and top officials of his firm Firestar Diamonds for causing losses of another Rs 321 crore to the Punjab National Bank.

Earlier on Tuesday, the Reserve Bank of India discontinued the practice of Letters of Undertaking and Letters of Comfort with regard to trade credits for imports with immediate effect. Letters of undertaking were issued fraudulently by employees at Punjab National Bank to grant a customer credit.

An Letter of Undertaking is a letter of credit, where one bank tells another that it will meet a customer’s liability.