The launch came eight days after North Korea fired multiple short-range ballistic missiles towards the East Sea -- also called the Sea of Japan -- as part of what it later described as a joint firepower drill, AFP reported.
It also followed Pyongyang’s rejection this week of a resolution by the UN nuclear watchdog demanding that it halt its nuclear activities.
“The North has fired an unidentified projectile into the East Sea,” South Korea’s Joint Chiefs of Staff said in a statement.
The office of the Japanese prime minister also confirmed the launch, saying on X that the projectile was a “suspected ballistic missile”.
Japan’s defense ministry later said the projectile had “already fallen”, without giving further details.
North Korea accused “hostile forces” of seeking to end the country’s nuclear program during this week’s General Conference of the International Atomic Energy Agency (IAEA).
A foreign ministry spokesperson said the IAEA resolution “has no effect on the DPRK’s position as a nuclear weapons state”, using the acronym for North Korea’s official name.
North Korea has legally enshrined its status as a nuclear-armed state, with its leadership declaring the country’s atomic arsenal permanent and irreversible.
US President Donald Trump said in August that North Korea possessed 57 “very powerful” nuclear weapons, while South Korea has put the figure at between 80 and 120.