Satellite photos published on Monday appear to show North Korea revamping a facility outside of Pyongyang used to build intercontinental ballistic missiles (ICBMs), the Washington Post reported.

American experts believe the facility in Sanumdong was responsible for the construction of the communist dictatorship’s latest model of ICBM, the Hwasong-15, and may be speeding up construction of liquid-filled ICBMs, considered less of a threat than their solid-filled counterpart.

Pyongyang officials claimed during its debut the Hwasong-15 can target the American mainland from North Korean territory.

The report surfaces about a week after the North Korea monitor site 38 North found evidence that the Kim regime had begun shutting down the Sohae Satellite Launching Station, previously used to construct ICBMs. The back-to-back revelations follow a pattern that North Korea appears to be following with its nuclear facilities, as well, very publicly shutting down its Punggye-ri Nuclear Test Site while satellite evidence shows renewed activity at the Yongbyon nuclear material enrichment facility.

Anonymous American officials told the Washington Post that intelligence officials have evidence that “work is underway on at least one and possibly two liquid-fueled ICBMs at a large research facility in Sanumdong,” one of them appearing to be a Hwasong-15. Experts observing the satellite images told the newspaper that employee movement at the facility was consistent with work being done to construct such a missile.

“It’s active. We see shipping containers and vehicles coming and going,” Jeffrey Lewis, director of the East Asia Nonproliferation Program at the James Martin Center for Nonproliferation Studies, told the Washington Post.

Reuters, which also reported on the new images, cited an American official who confirmed the evidence that the facility was working on a missile, but suggested that the model being built was less of a concern for Washington than it could potentially be, as a liquid-fueled ICBM does not “pose nearly the threat that a solid-fuelled one would because they take so long to fuel.”

The BBC added, citing an expert observer, that the images showing this construction were taken as dictator Kim Jong-un met with South Korean President Moon Jae-in and American President Donald Trump, promising “denuclearization of the Korean Peninsula.” Kim never specifically defined what he meant by “denuclearization” and the Kim regime has in the past used the term to mean the removal of American assets from the Korean peninsula, as the U.S. is a nuclear power, not necessarily an end North Korea’s illegal nuclear weapons program.

The Washington Post report comes nearly a week after 38 North published its findings on the Sohae facility, which is believed to be used to test and launch, but not necessarily construct, missiles and satellites. Satellite images of Sohae showed workers appearing to dismantle key infrastructure at the site, including the rail-mounted processing building where the projectiles are prepared before they are sent to launch. If completed, dismantling of Sohae makes it impossible to launch long-range missiles from that facility.

A day after the release of that report, Secretary of State Mike Pompeo told the Senate at a hearing on North Korea that American officials believe Pyongyang is continuing to produce fissile material which could be used in both nuclear energy generation and nuclear weapons.

“Our objective remains the final, fully verified denuclearization of North Korea, as agreed to by Chairman Kim Jong-un,” Pompeo asserted, adding, “We absolutely need every single nation to maintain the enforcement of those sanctions to which every nation is committed.” Even with those sanctions, he noted, nuclear activity has not ceased nationwide.

Pompeo’s remarks followed the publication of a report in the Asian affairs magazine the Diplomat asserting just that – that North Korea was operating a secret facility known as “Kangson” to enrich uranium. Experts believe Kangson is operating in tandem with Yongbyon, the flagship enrichment facility, even though the regime of Kim Jong-il claimed to have shut that facility down years ago.

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