Personal details, relating to half of South Korea's population, have been stolen by hackers, including full names, account names, passwords and resident registration numbers.
The hack was revealed after 16 people were arrested for stealing data from a number of online game and movie ticket sites. They are said to have set up targeted attacks on registration pages of the sites to siphon off the personal details.
North Korea has tasked 200 agents with the job of posting negative comments online, often using stolen online identities, in a bid to undermine the morale of their neighbours in the South.
The brigade of NORK trolls is part of a brigade of 3,000 cyber warriors and hackers that make up the Reconnaissance General Bureau information warfare force, according to the Police Policy Institute.
South Korea will be stepping up its cooperation with the United States, particularly in the area of cyber warfare, to better deal with emerging threats. This comes on the back of last month's cyberattack, which was the largest the country had witnessed in two years.
The Yonhap News Agency reported Monday the South Korea's defense ministry said it will increase its cyber warfare forces and develop deterrence scenarios in partnership with the U.S. The deterrence methods will help the country be more prepared against an unprovoked attack in times of peace and war, it noted.
Last week, over 32,000 computer servers operated by South Korean financial institutions and broadcasters were compromised by a piece of malware.
Some reports have revealed that the attackers might have utilized a security hole in the products of AhnLab, a South Korean antivirus company whose solutions are used by many of the victims of the attack.
