The Anonymous hacking collective has launched the second major assault on North Korean websites.
Hackers from the amorphous group claimed to have targeted a variety of North Korean news and information sites.
Websites including uriminzokkiri.com, minjok.com, jajusasang.com, and paekdu-hanna.com - all North Korean-controlled news sites - are offline.
The hackers announced the hack from an official Pyongyang Twitter account which has been under their control for more than seven days.
Last week the hacking group successfully attacked the official Uriminzokkiri Twitter and Flickr page, and claimed to have downed internal news services after gaining access to a mail server.
On some of the sites a Photoshopped picture of NK leader Kim Jong Un with the head of a pig was on display.
Anonymous said that further attacks were to come, while one note posted before the hack said that the group had members inside the country.
The claim comes after tech writers questioned whether an outside hacker could attack the North Korean "intranet", which is not supposed to be connected to the outside world.
"We have a few guys on the ground who managed to bring the real internet into the country using a chain of long distance WiFi repeaters with proprietary frequencies, so they're not jammed (yet). We also have access to some N.K. phone landlines which are connected to Kwangmyong through dial-ups. Last missing peace of puzzle was to interconnect the two networks, which those guys finally managed to do."
The hacks come in the context of increasing tension on the Korean peninsula, as the secretive regime continues to threaten the US and South Korea with nuclear war.
Meanwhile a worsening cyber way between the two sides - and Anonymous - is said to be further destabilising the region.
"The side effects and results of actions in the cyber world are difficult to estimate and manage, which makes them even more dangerous," Jarno Limnéll, doctor in military science and director of cyber-security for Stonesoft, based in Finland, told the Huffington Post UK.
"Cyber activities play a significant role in the rapidly escalating chain of events – which, in the worst case, may lead to large-scale warfare."