Assistant Commissioner of Police (Cyber Crime) Vivek Ranjan Rai said that an investigation has been launched into the crime that took place over a period of five days in June.

"The IT manager -- Sumit Kumar Srivastava -- of the Nainital Bank's branch in sector 62 submitted a complaint at the Cyber Crime police station here, informing that between June 16 and 20 some unknown persons hacked the servers of the bank," Rai said.

The official said that the perpetrators hacked the servers to take control of the login ID and password of the bank passenger. With the access they entered the bank's Real Time Gross Settlement (RTGS) channel and transferred Rs 16.5 crore to separate accounts.

Srivastava reportedly noticed the missing money in the heist while tallying the balance sheet for June.

The balance sheet on June 17 was found to be short of Rs 3,60,94,020 during a regular audit of the RTGS channel, Srivastava's complaint was cited by NDTV. It said that the fraud came to light when even after several days the balance sheet could not be matched.

The probe so far suggests that the funds were transferred into 89 different bank accounts, he added.

Police have formed a special term to investigate the matter, Rai said, adding that arrests in the case would be made soon and the stolen amount would be recovered.

(With PTI inputs)