North Korea fired an intercontinental ballistic missile (ICBM) into the Sea of Japan on Dec. 18, less than 24 hours after launching a short-range missile, South Korea's Yonhap News Agency reported.
This represents North Korea's fifth ICBM launch of 2023.
The South Korean military said that the missile was fired from the Pyongyang region at 8:24 a.m. local time at a lofted angle. The ICBM flew about 1,000 kilometers before it hit the water.
The military is still investigating how high the missle flew and whether it used solid fuel.
According to Yonhap, South Korea's First Deputy National Security Adviser Kim Tae-hyo had recently warned that North Korea might launch an ICBM this month.
South Korea's Joing Chiefs of Staff earlier reported that North Korea had fired one short-range ballistic missile into the sea on Dec. 17, the 12th anniversary of the death of former North Korean leader Kim Jong Il.
The Joint Chiefs said that the missile was fired from Pyongyang at around 10:38 p.m. local time, and that it flew for approximately 570 kilometers before landing in the Sea of Japan.
At the time of that launch, there was speculation that North Korea had fired an ICBM, but the Joint Chiefs confirmed that it was a short-range weapon that time.
South Korea called the launch a "clear" violation of U.N. Security Council resolutions prohibiting North Korea from using ballistic technologies.
"While elevating our alert readiness, our military is maintaining a full readiness posture by closely sharing data on the 'North Korean ballistic missile' with the United States and Japan," the Joint Chiefs said.
The three allies have bolstered their trilateral security partnership in the wake of escalating tensions with North Korea.
The countries have also monitored weapons transfers between North Korea and Russia. In a joint statement issued Oct. 25, the U.S., South Korea, and Japan condemned the arms agreement bewteen Moscow and Pyongyang.
Russia and North Korea have officially denied reports of an arms deal, though intelligence reports and media accounts indicate that weapons transfers have begun.
The U.S. believes Pyongyang is supplying Moscow with weapons for its war against Ukraine in exchange for advanced Russian technologies that can improve North Korea's nuclear program.
On the same day that North Korea launched the missile, the Russian Defense Ministry announced that its Strategic Missile Forces loaded an RS-24 Yars ICBM into a silo in Kaluga Oblast.