SEOUL, South Korea — South Korea said Tuesday that rival North Korea has a 6,000-member cyber army dedicated to disrupting the South's military and government, a dramatic increase from an earlier estimate of 3,000 such specialists.
Without elaborating, Seoul's Defense Ministry also said in a report that North Korea may also have gained the ability to strike the U.S. mainland because of its progress in missile technology demonstrated in recent long-range missile tests. It also said North Korea is advancing in efforts to miniaturize nuclear warheads to mount on such missiles.
There is considerable mystery, and outside debate, about the state of North Korea's opaque nuclear and missile programs, which it has persisted in pursuing for decades despite widespread domestic poverty and heavy international sanctions and criticism.
North Korea has conducted three nuclear tests since 2006, the most recent in early 2013, and experts believe it has a handful of crude nuclear bombs. Many outside observers speculate that it has not mastered the technology to make the bombs small enough to put on long-range missiles, although some say it may be able to arm shorter-range missiles with warheads.
North Korea has conducted several long-range rocket tests, which are seen as covers for banned tests meant to develop missiles that could hit mainland American shores. North Korea says its launches are meant to put peaceful satellites into orbit, and that its nuclear program is crucial to protecting itself from U.S. hostility.
The South Korean Defense Ministry report said North Korea's 6,000 cyber warriors are dedicated to "paralyzing the South psychologically and materially" and have been conducting cyberattacks to disrupt the South's military operations and main government systems. It didn't describe how it made its assessments.
The United States accuses North Korea of a cyberattack on Sony Pictures over a movie depicting the fictional assassination of the North's leader, Kim Jong Un. Washington has slapped sanctions on government officials and North Korea's defense industry. There are doubts in the cyber community, however, and North Korea has denied any involvement in the breach of tens of thousands of confidential Sony emails and business files.
Former South Korean Defense Minister Kim Kwan-jin said in 2013 that North Korea was operating a cyberwarfare staff of 3,000. South Korea accuses North Korea of conducting at least six high-profile cyberattacks since 2007 and many more unsuccessful attempts to infiltrate computer systems of businesses and government agencies.
The Korean Peninsula is still in a technical state of war because the 1950-53 Korean War ended in an armistice, not a peace treaty. There are 28,500 U.S. troops stationed in the South as a deterrent against a North Korean attack.