WORRYING images of a top secret shipyard show North Korea is ramping up construction of a fleet of nuclear subs capable of striking anywhere in the world.
The satellite photos reveal increased activity at a military facility in a security leak which will leave dictator Kim Jong-un fuming.
The photos show vessels and cranes needed to haul a missile out to sea for launch, according to experts at a Washington-based think tank.
The satellite photos taken over Sinpo South Shipyard seem to confirm North Korean state media reports from July about a highly-secretive submarine.
“There is no conclusive evidence at the moment that this is a near-term certainty,” an expert said of a possible missile test.
Once a submarine is built, it would take at least a year before it’s ready, according to one expert.
The construction and commissioning of a true SSB (ballistic missile submarine) capability would represent a significant advancement of the North Korean ballistic missile and nuclear threat.
It would also complicate defence planning in the region, given the difficulties of tracking and targeting subs.
In the last year, 15 cranes have been installed at the shipyard, NBC reported.
South Korean national newspaper, Chosun, earlier claimed North Korea is building 3,000-tonne submarines.
It is suggested it could be capable of launching ballistic missiles which can easily reach the United States and beyond.
A senior military spokesman said: “A large quantity of components presumably needed to build a 3,000-tonne sub, which the North has been developing, have turned up recently at a shipyard in Sinpo, South Hamgyong Province.
“We’ve also spotted a floating dock deployed off Sinpo, apparently for a missile test.”
Satellite imagery taken in March showed cylindrical components.
It is speculated they are bulkheads which will be welded together to form the submarine’s hull.
None of the components could be seen from space last year.
A South Korean military spokesman said: “This suggests that the North has kept building a new sub and testing a submarine-launched ballistic missile.”
This means construction has been underway just weeks after the June Singapore summit between Kim and US President Donald Trump and the one in Vietnam last February.
The North already has a 2,000-ton submarine. This is said to be capable of carrying only one ballistic missile.
Yet the new sub could deploy three or four.
This is still far behind the capability of other nuclear powers.
The Royal Navy for example has four 15,000-ton subs that each can launch 16 Trident nuke missiles.
The United States Navy, meanwhile, has 14 Ohio class boats, which are about similar size and firepower as the British ones.
But while the new sub would not match those possessed by existing nuclear powers, the building of the North Korean vessel would drastically increase its strategic strike capability.
Any launch would be hard to detect and it might be unclear which nation fired the missile.
Gen Terrence O’Shaughnessy, the commander of the US Northern Command, said in a hearing at a US Senate Armed Services Subcommittee the North’s deployment of intercontinental ballistic missiles is “imminent”.
Gen O’Shaughnessy said it is almost certain they are designed for an attack on the US mainland.
He said “He almost certainly has plans to use them against our homeland should a conflict erupt on the peninsula.”