Google Earth and Strategic Sentinel Satellite images of the islands being built by North Korea that possibly contain military establishments.

North Korea is building artificial islands and what look like military installations in the Yellow Sea, the Los Angeles Times reported Wednesday.

Satellite images show that the North has been building the islands for about five years around Sohae, a city about 70 miles northwest of Pyongyang. Sohae is a research and development center for intercontinental ballistic missile (ICBM) technology.

About five years ago, three of the islands were merely rocky specks with trees, and two others were nothing but sand. But as of December 2016, the five islands seem to have features consistent with military facilities, such as wide roads and rectangular concrete lots.

But the islands and installations are not uniform in size or structure, and so their purposes are not clear and could all be different. They could be used for missile launches, anti-aircraft weapons or anti-ship weapons. They could also simply be used for agriculture.

“We can’t make definitive statements as to what these islands are being used for,” Ryan Barenklau, chief executive of Strategic Sentinel, told the Times. But he added that they’re probably for military purposes.

The islands have winding roads that could be used for transporter erector launchers, which are large, missile-bearing trucks. Light patches on the rectangular lots also indicate heat-resistant cement for launch pads.

However, building Transporter Erector Launcher (TEL) pads on these islands would not be strategically wise. Anti-air missiles and missile silos would be the wiser choice, but it’s still difficult to tell from the satellite images.

The islands also “have observation areas, for someone like [the country’s leader] Kim Jong-un to observe a missile launch,” Barenklau told the Times. “Every time we see VIP buildings, that tells us there’s most likely a military application, because Kim Jong-un likes to view the operations of whatever they’re building.”

Barenklau said that they couldn’t tell what the purpose of the islands were at first, “but when we saw the observation decks, we thought, those are military.”

But “the North Koreans build just about everything for dual purpose,” Steve Sin, a researcher on unconventional weapons and technology at the University of Maryland, told the Times. “So, building something that is of military use on an agricultural project is certainly within its usual pattern.”

Some of the islands appear to be part of a North Korean project consisting of fish, duck and oyster farms. North Korea has even been known to test missiles at civilian airports.

China too has built several islands in recent years to sustain it’s territorial claims in the South China Sea. Beijing has repeatedly said that the islands are only for civilian purposes, but satellite imagery also points to military establishments as well.

North Korea has dramatically increased its missile launch attempts in the last three years. On April 28, North Korea attempted another missile launch, the ninth attempt since President Donald Trump took office.

But the US’s rhetoric towards Pyongyang has cooled since Vice-President Mike Pence said that the administration would not talk with North Korea, and that “the sword stands ready.”

Secretary of State Rex Tillerson recently said that Washington would like to engage diplomatically with Pyongyang. On Monday, Trump said he’d be “honored” to meet Kim Jong-un.

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