South Korea’s media regulator said Sunday that around 35,000 Korean Facebook accounts had been compromised in the latest security breach at the social networking site, pledging to continue investigating the matter and to take action as needed.

The Korea Communications Commission said Facebook had informed the regulator that an estimated 34,891 accounts had been compromised Sept. 14-25, exposing sensitive information such as names, email addresses, phone numbers and other information visible on users’ Facebook profiles.

The KCC said it has ordered Facebook to immediately inform the affected users of the data breach and to guide them on the steps they need to take to protect their personal data.

“The KCC will continue its investigation to determine the exact number of Korean Facebook users affected, the motives for the hacking attack and remedial measures. We will take legal action if Facebook is found to have breached the Act on Promotion of Information and Communications Network Utilization and Information Protection,” it said.

The findings come after Facebook disclosed the discovery of a security issue two weeks ago that it believed to have affected nearly 50 million accounts. The social network operator on Friday revised that estimate to 30 million, but user concerns over privacy and security on Facebook continue to loom large.

By Sohn Ji-young (jys@heraldcorp.com)