According to CNN, satellite footage shows the Yeongjeo-dong base is still active, and another base seven miles away is being upgraded.
The Middlebury Institute of International Studies at Monterey told CNN that the images indicate that North Korea was building an extremely large underground facility in 2017 and that this facility was still under construction as of August 2018.
"Moreover, in the past year North Korea has significantly expanded a nearby facility that appears to be another missile base".
Trump said on Saturday he hoped to hold a second meeting with Kim early next year and United States national security adviser John Bolton said the lack of progress with North Korea made a second summit necessary, likely to be held in January or February.
These steps have triggered a fierce backlash from many conservatives in South Korea, who argue that South Korea's liberal government led by President Moon Jae-in should not have agreed to such conventional arms reduction programmes at a time when North Korea's nuclear threats remain unchanged.
Experts told the USA news network that the site´s location made it suitable to host North Korea´s newest long-range missiles, including ones that could carry nuclear warheads.
People lie, satellite images don't-hence why the USA and South Korea are closely monitoring a new suspected missile site near North Korea's central border with China.
Such activities are said to have been continuing even after the historic summit between the leaders of North Korea and the U.S.in June.
"That's why I think the president thinks that another summit is likely to be productive", Bolton said during the Wall Street Journal's CEO conference. "Meeting Kim again only validates Kim's strategy of using Trump to play for time and sanctions relief, and keep North Korea on the pathway to becoming a de facto nuclear weapon state", Medeiros told The New York Times.