Websites in North Korea were shut down early on Thursday after the anarchist group Anonymous reported stealing secret data from the reclusive communist state on Pyongyang’s missile programs.
U.S. officials who monitor North Korean websites said despite the domestic shutdown, North Korean-run foreign websites and social media accounts appeared to be uninterrupted.
The disruption of the websites appears linked to claims by Anonymous on Tuesday that it had broken in to North Korean government sites and obtained secret documents on the North Korean missile program.
The North Koreans operate one of the largest missile manufacturing industries in Asia and build several types of short-range Scud missiles, a medium-range Nodong missile and long-range Taepodong-2 and mobile KN-08 missiles.
The hacker group has not published the documents so far, which likely are in Korean.
Nine additional websites including Air Koryo (http://www.airkoryo.com.kp) were also dark.
The sites remained inactive as of Thursday afternoon.
The Shenyang, China-based Uriminzokkiri and a related television website were working, however.
Officials speculated that the sites were taken off line as cyber security specialists unravel the Anonymous cyber breach.
Anonymous has claimed in the past to have hacked into North Korean web sites and issued threats to make additional digital forays into those networks.
Other North Korean websites that were operating normally included Anti-Imperialist National Democratic Front (AINDF) (http://www.aindf.com/) and Kim Il Sung Correspondence College (http://www.ournation-school.com). North Korea's official Twitter, YouTube, and Flickr accounts also were online.
Meanwhile, North Korea’s political police and security service warned defectors from the country that they faced "substantial measures."
The Ministry of People’s Security statement, published by KCNA, on Wednesday said North Korea was moving ahead as an "independent and powerful" country despite efforts to isolate the regime of Kim Jong Un.
"A handful of human scum is moving desperately to deter this progress," the statement said.
The statement also criticized South Korean President Park Geun Hye and other "puppets" in South Korea for "openly putting to the fore human scum belonging to the organizations of diehard defectors from the north, painting them as ‘experts in north Korean issue’ and instigating stepped-up criticism."
The statement criticized defectors for claiming that copies of Adolf Hitler’s Mein Kampf were distributed to North Korean leaders and for "belittling" Kim Jong Un.
"The army and people of [North Korea] regard it as shame to make mention of defectors from the north, a group of wild dogs in human form," the statement said.
"The army and people of [North Korea] are strongly calling for punishing those human scum as early as possible as they are going hysteric as servants escalating confrontation with fellow countrymen, far from trying to redress their crime-woven past with death," the statement said.
"There are daily requests from home folks and kinsmen of those defectors asking to let them kill human scum with their own hands."
The statement then said the ministry "is determined to take substantial measures to physically remove despicable human scum who are committing treasons at the instigation of the South Korean puppet authorities and the gangster-like U.S."
North Korea is known to operate special operations teams capable of conducting assassinations abroad.
There were several attempts to kill defectors in South Korea.
Recently, several North Koreans who falsely defected to South Korea were shown on North Korean state television, an indication that the regime has dispatched agents posing as defectors and probably has learned information about the locations of defectors.
Recently a group of several journalists who left North Korea met with U.S. journalists in Washington.
Hundreds of North Korean defectors have managed to escape North Korea, mainly through China and South Korea.
Several recent books by North Korean defectors also have revealed the horrors of the vast prison camp system operated by the regime in Pyongyang.
The United Nations recently authorized a special commission to investigate North Korean human rights abuses.