Hana SK Card said the personal information of about 200 of its customers has been compromised by a telemarketer, the latest in a series of data leaks at financial institutions.

The Financial Supervisory Service, however, said the leak would be of a far larger scale than reported by the credit card company.

“Hana SK Card said that the data of some 200 clients has been compromised in its initial report but our investigation into the case says the number is at least 90,000,” an FSS official said.

“Our inspection team has been sent to the company today to track the leak and examine the damage caused,” he added.

The credit card company said personal information including names, addresses and resident numbers has been exposed but said details such as account numbers, financial transaction history and passwords have been kept sealed.

The telemarketer at the company is said to have extracted customer information to sell for some extra cash.

“We got a call from an anonymous informant Thursday who said an employee of ours has exposed client details. We’re still conducting internal inspections to get to the bottom of this,” an official at Hana SK said.

The violation follows previous information leaks at Samsung Card, SK Communications, Nonghyup and Hyundai Card from this year. Samsung Card has been under fire for its attempt to downplay a leak of up to 800,000 clients earlier this month.

Hyundai Capital was recently punished for the leak of some 1.8 million customers by hacking in April, in which the hacker extracted personal information from the company’s network and even informed the management of the intrusion.

The regulator has pledged to step up preventative efforts and raise awareness of how to protect personal information at both the client and company end.

By Cynthia J. Kim (cynthiak@heraldcorp.com)