North Korea accused The South on Monday of blocking its people from accessing online social-networking sites launched by the secretive communist country.
Pyongyang opened a Twitter account on August 12 after its foray into popular video-sharing website YouTube, prompting a game of online cat-and-mouse with Seoul which has struggled to stop its citizens following The North's official website, Uriminzokkiri.
South Korea has been "crazy to stop its people from gaining access to video and messages posted on our YouTube and Twitter," said a statement seen on the North's website.
"This proves the group of traitors is an anti-unification faction, which does not want (inter-Korean) dialogue and cooperation," it said, adding the South's "dirty" move will only aggravate confrontation on the peninsula.
The North has used its Twitter account, opened under the name @uriminzok, to link to stinging statements against Seoul and the US posted on its official website.
Seoul has warned South Korean web users they face punishment for seeking to reply to or retweet North Korean messages, but Pyongyang has quickly gathered more than 10,000 followers.
North Korea, one of the world's most controlled states, is believed to have an elite unit of hackers, but few of its citizens have access to a computer, let alone the Internet.
The North also launched its Facebook page on August 19 to post video links, wallpostings and pictures of happy picnickers, grassy parks and colourful landmarks from across Pyongyang.
Facebook is more expansive than Twitter as it allows users to upload a wide variety of multimedia contents. But the North's Facebook disappeared only four days after its launch.
The (South) Korea Communications Standards Commission said the US-based Facebook operator appeared to have cancelled the North's account because it did not meet required standards.