According to a Reuters report, the bank claimed that it had been hacked by "cyber criminals" who were responsible for the three unauthorised remittances which were made using the SWIFT banking platform.
SWIFT is headquartered in Belgium and provides a network that allows financial institutions in more than 200 countries to send and receive information about financial transactions to each other. Most SWIFT members are banks, and trading institutions, according to security expert Matthieu Suiche who runs a security firm in the United Arab Emirates.
He described it as a conspiracy involving a number of countries and while there was no evidence of staff involvement, "we are very clear now the account holders are part of this conspiracy".
The news of the City Union Bank fraud comes on the heels of an announcement from India's Punjab National Bank that it lost US$1.7 billion in a fraud where officials used to take percentage commissions in lieu of issuing letters of undertaking and foreign letters of credit to diamond czar Nirav Modi and his partner Mehul Choksi and their firms.
The City Union Bank said that it had been able to block one of the remittances of US$500,000 being sent to a Dubai-based lender through a Standard Chartered Bank account.
Another transfer of 300,000 (US$372,150) was sent through another Standard Chartered Bank account in Frankfurt to an account in Turkey. The recipient had blocked finalisation of the transfer, the report said.
Dr Kamakodi identified the recipient bank of a third transfer as being the Zhejiang Rural Credit Co-operative Union in Hangzhou, China. This transfer was for US$1 million and was sent through an account in the Bank of America.
Reuters said more than 100 financial institutions in India are connected to SWIFT, including the Reserve Bank of India, the country's central bank.