Computer hackers have breached Citigroup’s network and accessed data on hundreds of thousands of bank-card holders in North America, Citigroup has said.
About 1pc of the bank’s card customers have been affected by the breach on Citi Account Online, which was discovered last month during routine monitoring.
The customers’ data that has been viewed includes their names, account numbers, email addresses and contact information, Citi said.
Information such as birth dates, card security codes, card expiration dates and social security numbers have not been compromised.
A US-based spokesman said the bank is contacting customers who have been affected by the breach, and that Citi has put procedures in place to prevent a repeat of "this type of event."
Citigroup has also notified law-enforcement officials.