SEOUL • The factories have innocuous names, but analysts say several ostensibly civilian facilities visited by North Korean leader Kim Jong Un recently are also being used to build ballistic missile launchers and other weapons.

North Korean state news agency KCNA yesterday released reports of Mr Kim providing "field guidance" at a number of factories and cities, without saying when the visits took place.

The reports only mentioned economic elements, but 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, say analysts at the James Martin Centre for Non-proliferation Studies (CNS) in California.

"This is the heart of North Korea's defence industry," CNS researcher Jeffrey Lewis told Reuters.

"These are the kinds of visits we saw in 2016 and 2017 as North Korea moved towards ICBM testing."

Among the sites Mr Kim visited was the February 8 General Machine Factory, which has been used to build ballistic missile launchers.

The factory was the site of the launch in July 28, 2017, of a Hwasong-14 ICBM that Mr Kim observed.

"North Korea has usually tried to hide this facility by not naming it," Dr Lewis said. KCNA said Mr Kim called for a "higher modernisation plan" for the factory while he watched a range of daily necessaries being produced.

Mr Kim also visited the Kanggye General Tractor Plant and the Kanggye General Precision Machine Plant, KCNA said.

Both plants are linked to the defence industry and may have played a role in the missile programme, the CNS analysts said.

Photos from the tractor plant show Mr Kim standing next to a "flow-forming machine" that highlights the potential dual use nature of the factories, said Mr Joshua Pollack, another CNS researcher.

Mr Kim has declared his nuclear force "complete" and announced an end to tests of long-range missiles and nuclear weapons. But at the same time, he has called for more operational weapons.

North Korea "remains an extraordinary threat", Acting US Defence Secretary Patrick Shanahan told regional defence chiefs in Singapore yesterday.

REUTERS