The state data protection agency has launched an investigation into the nation's second- and third-largest mobile carriers, KT and LG Uplus, amid allegations of subscriber data breaches.

The Personal Information Protection Commission(PIPC) said in a press release Wednesday that the allegations emerged following multiple cases of KT users reporting unauthorized mobile payments.

The agency also mentioned U.S. cybersecurity magazine Phrack recently reporting on the alleged hacking of the two South Korean telecom companies.

The PIPC said it verified the facts with the carriers in question via document requests, interviews and information sharing with related agencies.

The agency plans to look into details of the reported incidents and verify the alleged breach during its investigation.