International hackers' collective Anonymous again broke into North Korean propaganda websites on Sunday. The "hacktivists" had previously attacked pro-North Korean sites and released the personal information of subscribers.
Anonymous also threatened to launch massive cyber attacks on the anniversary of the Korean War armistice.
Anonymous tweeted that it hacked the website of North Korean radio station Voice of Korea together with links to the damage done.
It also tweeted blow-by-blow updates of its attacks of the official KCNA news agency and propaganda website Uriminzokkiri.
The attack stopped in the early afternoon. "This Attack is very small operation," the collective tweeted. "It will be very huge op on 6/25," the anniversary of the outbreak of the Korean War.
The hackers warned of additional attacks in June, listing 31 North Korean websites that are to become targets including the State Security Department and military's intranet.