The evidence obtained this month is the latest to suggest ongoing activity in North Korea's nuclear and missile facilities despite talks with the United States and a June summit between North Korean leader Kim Jong Un and US President Donald Trump.
North Korea shows off its missiles in a parade.
In a statement by an unnamed foreign ministry spokesman, carried by North's Korean Central News Agency (KCNA), Pyongyang criticised Washington D.C. for "seeking unilateral and forced and "gangster-like demand for denuclearisation", Yonhap News Agency reported".
Liquid-fueled ICBMs, such as the Hwasong-15, require lead-time to make ready for launch and are therefore considered less destabilizing than solid-fueled rockets, which can quickly be prepared for a first strike.
"Jeffery Lewis, the director of the East Asia Nonproliferation Program at the James Martin Center for Nonproliferation Studies, who was also quoted by the Post, told ABC News, "[The Washington Post] is reporting on a leak that North Korea is constructing one or two ICBMs at Sanumdong.
Team Trump on Tuesday minimized revelations that USA spy agencies believed that North Korea was building new missiles in the same research facility that manufactured earlier ballistic missiles capable of reaching the US.
If the reported North Korean nuclear activity seems inconsistent with what went down at the meeting in Indonesia, it's because Trump oversold the progress he made there.
Lewis's group also published images of a large industrial facility that some US intelligence analysts believe to be the Kangson uranium enrichment plant.
Lunar Eclipse: Skygazers Await Century's Longest 'Blood Moon'
Kiwi eclipse watchers were disappointed this morning when the moon disappeared behind clouds at the crucial moment. For about half the world, the "blood moon" will be partly or fully in Earth's shadow from 1:14 p.m.to 7:28 p.m.
Government officials believe North Korea is continuing to manufacture missiles in a facility near its capital of Pyongyang. "That was certainly the case during the Cold War when the USA and USSR continued to build missiles and nuclear weapons even while negotiating arms reduction agreements".
A U.S. official who spoke to Reuters said one photo showed a truck and a covered trailer similar to those used to move previous North Korean ICBMs.
"New images just today show that North Korea has begun the process of dismantling a key missile site, and we appreciate that", Trump said, an apparent reference to images of the Sohae Satellite Launching Station published Monday by the prominent monitoring group 38 North.
"Regime survival and perpetuation of Kim family rule" are Kim's guiding principles, he said.
Ministers from the two Koreas agreed in April to push for a unified delegation from both countries to parade together in the opening ceremony at the Asian Games, to be staged in August and September, amid signs of easing tensions over Pyongyang's nuclear ambitions.
Pompeo, at the Senate hearing last week, sought to assure lawmakers that the disarmament talks with North Korea remained on track and that the effort to dismantle the country's nuclear arsenal was just getting underway.
"I'm afraid that at this point, the United States, the Trump Administration is being taken for a ride", said Sen. "Fissile Material" is uranium or plutonium that can be used to produce the nuclear fission reaction necessary for nuclear weapons.