North Korea has made significant progress on its nuclear capability with its plutonium stockpile reaching 50 kilograms, which is capable of making up to a dozen fission bombs, according to South Korea’s 2016 defense white paper released Wednesday,

The Defense Ministry’s biennial report said the communist state has scaled up its “Strategic Rocket Force” in charge of nuclear and missile warfare to 10,000 and cyber personnel to 6,800 as part of efforts to boost its asymmetric warfare capability.

The report assessed that Pyongyang has secured some 50 kilograms of weapons-grade plutonium, up from the 40 kilograms estimated in the 2014 edition of its white paper. The volume is sufficient to manufacture around 10 nuclear weapons, as one bomb generally requires 4 to 6 kilograms of the material.

“We have come up with this number based on when its nuclear reactor at Yongbyon began operation (and) how much plutonium it has obtained after using it for nuclear tests,” a Defense Ministry official said on the customary condition of anonymity.

The North has been ratcheting up its threats to launch an intercontinental ballistic missile capable of reaching the US mainland. On Sunday, Pyongyang vowed to fire the missile “anytime at anyplace,” and its leader Kim Jong-un said the regime has reached the final stage of its ICMB development. 

Reflecting Seoul’s mounting concerns, the paper underscored Pyeongyang’s increasing missile threat, describing for the first time that the North is developing the ICBM and submarine-launched ballistic missile and that it has finished deployment of the Scud-ER missile with a range of 1,000 kilometers.

The 2016 report described in detail information about Pyeongyang’s various ICBMs, including the KN-08 and KN-14 with a range of up to 12,000 kilometers as well as the SLBM that the North test-fired last August. Pyeongyang has yet to test-fire the KN-08 and KN-14, which were revealed during a military parade in 2012.

“We decided to classify the KN-08 and KN-14 as ICBMs because we want to track their development process,” the Defense Ministry official said. “It is part of our efforts to figure out the missiles’ capabilities and technological process.”

The white paper also noted that Pyongyang has made “considerable” progress in producing highly enriched uranium, another type of fuel for nuclear bombs. But the report did not provide information about the specific amounts of weapon-grade HEU -- a material produced by a centrifuge plant usually run in a secretive environment.

Meanwhile, North Korea has increased its number of cyberwarfare troops to 6,800 from 6,000 in 2014, said the paper, reflecting mounting concerns over the growing threat of North Korea’s cyberattacks targeting South Korea’s defense system and socioeconomic infrastructure.

Last December, the military intranet run by Seoul’s Defense Ministry was hacked for the first time, resulting in a number of military secrets being leaked. The ministry suspected Pyeongyang was behind the attack because the code used in the attack was similar to that previously used by North Korean hackers.

“Recently, the North Korea military has reshuffled its organization,” said the paper, adding that Pyongyang’s General Staff Department, equivalent to Seoul’s Joint Chiefs of Staff, has created a new organization dealing with intelligence operation and increased military personnel for the mission.

The paper noted that Pyongyang has increased the number of standing troops to 1.28 million in 2016 from 1.2 million two years earlier, highlighting the regime’s efforts to enhance conventional military power despite its decreasing population and shrinking economy.

Specifically, the army boasted 1.1 million troops, 80,000 higher than two years earlier. Among them, 100,000 were assigned to “strategic forces” dedicated to nuclear and missile warfare. The air force shrank from 120,000 to 110,000. The navy remained unchanged at 60,000.

North Korea’s army has increased the number of corps-level units to 17 from 15, and division-level units by one to 82, the paper said. The newly established units are dedicated to massive construction missions such as building highways and monuments idolizing Kim Jong-un, it added.

“North Korea believes that it will need a more unified command and control system for construction missions glorifying Kim’s legacy,” said the official. “They think the military is more suitable for doing such missions than civilian organizations.”

By Yeo Jun-suk (jasonyeo@heraldcorp.com">jasonyeo@heraldcorp.com)