North Korea has prompted concern among US officials with measures to increase defence
The activity took place on Thursday, according to the website 38 North which monitors the hermit state
Commercial satellite imagery taken of the Sohae Satellite Launching Station "indicate upgrades are in progress at North Korea's main space launch facility”.
Reports suggest that a new guard or observation positions and excavation near the launch pad, the purpose of which is yet unclear," the website 38 North said.
The site said: ”Natural-Colour and infrared imagery indicate there have not been any unreported rocket engine tests during the past month, and no preparations for a new engine test or satellite launch are apparent. No other activity of significance is noted at the site.”
"Low-level construction has been ongoing at the Sohae facility for the past three years and is an indicator of North Korea's long-term commitment to the facility and its space launch programs.”
It comes as North Korea showed it can “strike” American territories with its missiles.
There are fears that the hermit state is preparing for an imminent attack against the US as Kim Jong-un has begun ordering the rapid construction of protective walls.
New road construction and other upgrades are underway at North Korea's rocket launch site
Work is underway but there there is no sign of preparations for a rocket launch or an engine test
Kim Jong-un believes his nation is on verge of being hit by cruise missiles from the US.
He is ramping up efforts to make its defence air tight.
Donald Trump's administration is also increasing its rhetoric against Kim.
US ambassador to the UN Nikki Haley called on the international community to support the Trump administration’s efforts in the region.
She said: ”You either support North Korea or you support us, because that's what it comes down to.”
North Korea has said it will continue secret underground nuclear and ballistic missile tests
Assessing the North Korea nuclear threat
Experts say Seattle most likely target for attack by North Korea
North Korea Missile test site on Volcano
North Korea has said it will continue secret underground nuclear explosions and ballistic missile tests to bolster its military capability.
US officials fear that everything which has been done to halt Pyongyang’s aggression has “failed”, one former US government official declared.
Stephen Rademaker, the former assistant Secretary of State responsible for arms control, said: “North Korea successfully demonstrated for the first time that it could strike US territory in the Pacific.
“In the absence of good military options or a Chinese deus ex machina, the remaining options for eliminating the threat are limited. We’ve tried them all, and all have failed.