North Korea fired at least one ballistic missile towards the open sea on Friday, the South Korean military reported.
The launching or even testing of ballistic missiles by the secretive regime in North Korea is prohibited by UN resolutions.
The missile flew out to sea between the Korean peninsula and Japan, according to the top military command centre in Seoul. There were no further details.
Depending on their design, ballistic missiles can be equipped with a nuclear warhead.
North Korea, ruled by dictator Kim Jong Un, is largely isolated internationally due to its nuclear weapons programme.