Tving CEO Choi Joo-hee (최주희) apologised for a recent personal data leak incident.

In an apology statement issued on Tuesday, Choi said the company had failed to protect information that users had trusted it with, and that the responsibility lies entirely with Tving.

"After confirming the incident, Tving implemented the necessary response measures and is currently cooperating in good faith with investigations by the government and related agencies," she said. "We will transparently inform you of progress and follow-up measures," she added.

She also said Tving would take responsibility to the end for damage relief and user protection. She added that the company would recheck its security system from scratch to prevent a repeat.

Tving said it discovered signs of external intrusion in its system on June 1 and reported the breach the same day to the Ministry of Science and ICT and the Korea Internet & Security Agency (KISA). A joint investigation by Tving and KISA found that an unidentified hacker had made unauthorised access to a user personal information database and sent files outside, which was confirmed on June 2.

The leaked items include user IDs, names, dates of birth, gender, a resident registration number identifier (CI), a duplicate subscription identifier (DI), mobile phone numbers, email addresses, refund bank account numbers and passwords. The last four digits of mobile phone numbers, part of email IDs, refund bank account numbers and passwords were leaked in encrypted form. The scale of the leak was not disclosed.

The Ministry of Science and ICT convened an emergency meeting of its breach incident investigation deliberation committee on Tuesday, judged it a serious incident, formed a joint public-private investigation team and began an investigation. The team includes the ministry, KISA and private-sector experts in forensics and cloud services, and it plans to disclose the results to the public.

Tving is providing individual notices to affected users. It is also operating a customer service centre for damage relief procedures.