SEOUL - The factories have innocuous names, but analysts say several ostensibly civilian facilities visited by North Korean leader Kim Jong Un recently are also used to build ballistic missile launchers and other weapons.
On Saturday, North Korea state news agency KCNA released reports of Kim providing "field guidance" at a number of factories and cities, without specifying when the visits occurred.
While the reports only mentioned economic elements, the sites help form the core of North Korea's arms industry, and have played a major role in developing its intercontinental ballistic missile (ICBM) technology, according to analysts at the James Martin Center for Nonproliferation Studies (CNS) in California.
"This is the heart of North Korea’s defense industry," CNS researcher Jeffrey Lewis told Reuters. "These are the kind of visits we saw in 2016 and 2017 as North Korea moved toward ICBM testing."
Among the sites Kim visited was the General Machine Factory, which has been used to construct ballistic missile launchers.
The machine factory was the site of the July 28, 2017 launch of a Hwasong-14 ICBM, which Kim personally observed.
"North Korea has usually tried to hide this facility by not naming it," Lewis told Reuters. "Sometimes it is unnamed; in other cases only the name of the plant manager was given."
KCNA reported that Kim called for a "higher modernization plan" for the factory, while he watched "varieties of daily necessity goods" being produced.
In January, Lewis authored a report listing the February 8 plant as one of several sites that North Korea's leaders had visited in the past without fully disclosing the location or purpose.
In many cases the visits appeared to be linked to efforts to reduce North Korea's reliance on imported chassis for its missile launching vehicles, the report said.
Kim also visited the Kanggye General Tractor Plant and the Kanggye General Precision Machine Plant, according to KCNA.
Both of those factories are linked to the defense industry and may have played a role in the missile program, the CNS analysts said.
Kim has declared his nuclear force "complete" and announced an end to tests of long-range missiles and nuclear weapons.
At the same time, however, Kim called for more operational weapons. Negotiations with the United States aimed at convincing North Korea to surrender its existing nuclear weapons and missiles have stalled.
In May, Kim oversaw the first flight of a previously untested weapon - a relatively small, fast missile experts believe will be easier to hide, launch, and maneuver in flight.