North Korea fired two unidentified projectiles from the eastern coastal city of Wonsan on Monday, South Korea's defence ministry said.
"The military is monitoring for additional launches and maintaining readiness," said South Korea's Joint Chiefs of Staff.
They were unable to confirm how far the projectiles flew or whether it was ballistic or rocket artillery.
The launches come just days after North Korea's Kim Jong-Un oversaw military drills.


Trump says he is unlikely to order Iran attack if talks progress
Train collision in Egypt’s Giza province kills 7, injures dozens
Saudi coalition says two Houthi missile launchers destroyed in Saada
Saudi energy ministry confirms attempted attack on Aramco building in Riyadh
COP31 climate summit to open in Turkey on Monday