Broadcast and telecom watchdog, Korea Communications Commission (KCC), announced Thursday it will strengthen its supervision and management of the country's three telecom companies--SK Telecom, KT, and LG Uplus--to further prevent personal data and information leaks. This follows news last week KT, the second biggest domestic mobile carrier, was found to have its system hacked. T wo men were arrested for allegedly stealing personal information of about 8.7 million customers and selling it to marketing companies.