The South Korean military says North Korea has fired multiple cruise missiles into the Yellow Sea west of the Korean Peninsula.
South Korea's Joint Chiefs of Staff said the launches took place from around 4 a.m. on Saturday. The South Korean and US militaries are conducting a detailed analysis.
The launches come after the inaugural meeting between the United States and South Korea of the Nuclear Consultative Group on Tuesday in Seoul to discuss Washington's extended deterrence.
On Wednesday, South Korean President Yoon Suk-yeol inspected a US nuclear-powered submarine capable of carrying ballistic missiles equipped with nuclear warheads in the southeastern port city of Busan. It was the first port call in the country by this type of US submarine in 42 years.
North Korea said it launched a new solid-fuel intercontinental ballistic missile known as Hwasong-18 on July 12. It also fired two short-range ballistic missiles into the Sea of Japan on Wednesday.
Pyongyang is apparently stepping up its confrontational stance toward Washington and Seoul as it is set to mark the 70th anniversary of the 1953 Korean War Armistice on July 27. Pyongyang sees the day as an occasion to celebrate what it calls its victory over the US.