North Korea test-fired an intercontinental ballistic missile into the sea in the direction of Japan on Thursday.

This marks the first time Pyongyang fired a ballistic missile into the sea since 2017.

The launch came following a statement from the U.S. and South Korean militaries saying that the People’s Republic was readying a flight of its largest intercontinental ballistic missile to date.

Japan’s Vice Defense Minister Makoto Oniki said that the missile reached a max altitude of 6,000 kilometers (3,728 miles) and was potentially a new grade of ICBM.

Japan’s coast guard, who warned seacraft in adjacent waters of possible falling projectiles, stated that it believed the missile flew for roughly one hour prior to landing in waters outside of Japan’s exclusive economic zone (EEZ).