North Korea fired a ballistic missile into the Sea of Japan, also known as the East Sea, Yonhap news agency reported.
The launch comes less than two weeks after Pyongyang's state media said North Korean leader Kim Jong Un had overseen a successful test of a solid-fuel engine for a "new type of medium-range hypersonic missile."
Japan also said it "appeared" that North Korea had fired the missile, adding that the country's coast guard believed the missile had gone down.
The launch is the third ballistic missile test so far this year, after Kim launched a solid-fuel missile in March and another one equipped with a maneuverable hypersonic warhead in January.
Last year, Pyongyang said it had successfully test-fired its first solid-fueled Intercontinental Ballistic Missile (ICBM) (the largest category of long-range ballistic missiles), hailing it as a key breakthrough in the country's nuclear countermeasures capabilities.
Solid-fuel missiles do not need to be fueled before launch, which makes them harder to detect and destroy, as well as faster to use./BGNES