SEOUL, Aug. 31 (UPI) -- North Korea is constructing a mobile long-range missile launcher that can be transported on rail tracks, according to multiple sources in North Korea.
The new system is being assembled at North Korea's June 4 vehicle factory and production began in 2016, Radio Free Asia reported Wednesday.
Engineers of Pyongyang's second economic commission began working on the launcher in May, one source on the North Korean side of Gangwon Province told RFA.
The plans to operate the mobile launcher were initially suspended due to the short supply of electricity in North Korea and scarcity of steel, the source said.
But under a plan, launched in 2014, to modernize North Korean weaponry, the project is now being managed by the second economic commission.
The vehicle factory has been manufacturing six railway-mounted launcher vehicles per month. The trains being used to transport the missile launcher would include about 8 to 14 cars, the source said, adding he had not directly observed the cars.
A second source based in North Korea's North Hamgyong Province said he had "heard the news" that North Korea was building vehicles to launch missiles that move over railways, according to RFA.
The source said the plan to transport the launcher on rail tracks might have been pursued after China refused to export heavy land-based vehicles to North Korea.
But North Korea's aging railroad system is not an optimal choice, other sources say.
North Korea's infrastructure is also vulnerable to damage due to severe weather.
Free North Korea Radio director Kim Seong-min told South Korean news service No Cut News heavy rains have been pounding on North Korea's North Hamgyong and Yanggang Provinces.
On Monday in the border city of Hyesan, a five-story apartment building collapsed and 80 people were subsequently injured or killed, according to Kim.