The incident came to light, late evening on August 13 after which the bank has shut down its systems for transactions as a precautionary measure.
The ATM switch system of the bank was hacked and Rs 94.42 crore were siphoned off between August 11 and August 13.
A complaint has also been filed at the Chatushrungi police station on Monday night by Subhash Gokhle, a bank official.
According to the complaint, hackers stole information of debit cardholders of the bank and carried out over 14,000 transactions from 29 countries. Bank officials suspect that that attack was done from Canada. However, they claim that the deposits of account holders are intact.
Although the bank claims customers are not affected, it is a huge loss to the bank as the money was withdrawn from a pool account. The transactions were carried on two different days, at first the systems were hacked on August 11 at 3 pm and around Rs 78 crore was transferred out of the country using VISA. Transactions of Rs 2.5 cr were done in India through NCPI and Rupay.
On August 13, at around 11.30 pm the server was hacked again and Rs 13.92 crore were transferred through Swift transactions, to the account of ALM trading limited at Hang Seng Bank in Hong Kong.
The money was later withdrawn through ATMs using bogus VISA cards. The police complaint also mentions the name of been ALM trading limited, where the money was transferred.
A case has been registered under several sections of the IT act and investigation is underway.