iStock/Thinkstock(WASHINGTON) — A U.S. official says that American intelligence has determined with a high degree of confidence that North Korea launched a two-stage intercontinental ballistic missile overnight, as the country had previously claimed.

An assessment of the launch remains ongoing, the official said, adding that North Korea’s missile advancements help to demonstrate the degree to which it can now fire its missiles on short notice.

After initial reports on the launch from North Korea, which commented upon President Trump tweeted about, U.S. Pacific Command had initially described the missile as an intermediate range ballistic missile, not intercontinental.

The trajectory of the launch matches information provided by South Korea: the missile was launched into a high-altitude trajectory of 1,730 miles and flew horizontally about 577 miles into the Sea of Japan.

The missile emerged from the north of Kusong, a city located in the far northwestern corner of North Korea, an area used for launches in the past.

U.S. officials had said Monday that they were anticipating a North Korean launch, but were keeping an eye on a facility in the eastern part of the country.

President Trump took to Twitter on Monday, before the Pentagon issued an official statement on the matter, to respond to reports that North Korea conducted another missile test.

“North Korea has just launched another missile. Does this guy have anything better to do with his life?” he tweeted late Monday, presumably referring to North Korean leader Kim Jong Un. “Hard to believe that South Korea … and Japan will put up with this much longer. Perhaps China will put a heavy move on North Korea and end this nonsense once and for all.”

The launch was North Korea’s 10th ballistic missile test this year.

A spokesman for Japan’s Cabinet said the North Korean missile landed inside Japan’s exclusive economic zone, which extends 200 miles from its shores.

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