North Korea fired a short-range ballista missile into the sea on Sunday, the South Korean military reported, as quoted by South Korean news agency Yonhap.
North Korea launched three new ballistic missiles on Saturday.
The first day of 2023 fire came from the Yongseong district in the capital Pyongyang and landed in the Sea of Japan, Yonhap said, citing the South Korean General Staff.
Military tensions on the Korean peninsula have risen sharply in 2022, with North Korea conducting almost monthly tests, including the firing of its most advanced intercontinental ballistic missile.
On Saturday, Pyongyang fired three short-range ballistic missiles, the Seoul military said, a day after South Korea successfully tested a solid-fueled space launcher.
This North Korean launch also followed the incursion of five North Korean drones into southern airspace earlier this week.
The North Korean incursion was the first such incident in five years and prompted an apology from Seoul's defense minister after his air force failed to shoot down a single drone despite the sending hunters on a mission that lasted five hours.