Bangalore Citigroup Inc confirmed a computer breach at Citi Account Online, giving hackers access to the data of hundreds of thousands of bank card customers.
The bank recently discovered unauthorized access at Citi Account Online through routine monitoring, a spokesperson told Reuters in an email.
The bank said about 1 percent of its card customers were affected by the breach.
The name of the customers, account numbers and contact information including email addresses of the affected accounts were viewed, Citi said.
Other information such as birth dates, social security numbers, card expiration date and card security code (CVV) was not compromised, Citi said.
"We are contacting customers whose information was impacted. Citi has implemented enhanced procedures to prevent a recurrence of this type of event," the spokesperson said.
The Financial Times first reported about the data breach.
(Reporting by Abhishek Takle in Bangalore; Editing by Vinu Pilakkott)