New Delhi, March 1: The Central Bureau of Investigation (CBI) on Thursday arrested yet another internal chief auditor (retired) of Punjab National Bank’s Brady House branch in connection with Rs 12,636 crore fraud, allegedly committed by companies of diamond merchants Nirav Modi and Mehul Choksi. Also Read - Nirav Modi's Bail Plea Denied Again, UK Court Extends His Custody Till June 27

The retired officer is identified as Bishnubrata Mishra, who was responsible for concurrent audit for the period of 2011-15 an the Mumbai branch. He was responsible for the audit of procedures and practices followed in the branch. Also Read - PNB Fraud: Non-bailable Warrant Against Nirav Modi's Wife

The investigation agency on Thursday questioned 13 more people, in addition to the interrogation of people in its custody. Also Read - PNB Scam: Antigua Govt Denies Knowledge of Indian Team to Fetch Mehul Choksi

The CBI on Wednesday arrested an internal chief auditor of the Punjab National Bank‘s Brady House branch. The internal auditor is identified as MK Sharma. He was also responsible for auditing the systems and practices of the branch.

Modi and Choksi are accused of obtaining fraudulent letters of undertaking from the Punjab National Bank (PNB). A retired PNB deputy manager was arrested to facilitate the fraud. Both Modi and Choksi have fled the country and are refusing to join the investigation.

CBI wrote a mail to Nirav Modi, asking him to come back to India and join investigation. Nirav Modi replied that he had a business abroad and hence, he can’t join the investigation.

On Tuesday, Nirav Modi and Mehul Choksi said that they can’t join the investigation as their passport had been revoked. The CBI said on Wednesday that Modi must contact the high commission of the concerned country and the agency would arrange his travel to the country.