North Korea fired multiple ballistic missiles toward the sea on Wednesday, following the launch of an unidentified projectile on Tuesday, South Korea's military said.
According to South Korea's Joint Chiefs of Staff, the missiles were launched from North Korea's eastern coastal Wonsan area toward the eastern waters.
It is suspected that the projectile detected on Tuesday was also a ballistic missile.
The South Korean military has ramped up its watch and is exchanging information with the US.
What lessons is North Korea learning from the Iran war?
To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video
Media outlets in South Korea reported that the projectile fired on Tuesday disappeared from South Korean military radar after showing an abnormal development in the early stage of the launch.
Pyongyang dashes Seoul's hope for warmer relations
The launches came as North Korea made it clear that it has no intention of easing the hostility with the South, shattering Seoul's hope for resuming dialogue.
On Tuesday night, Jang Kum Chol, first vice minister at Pyongyang's Foreign Ministry, said South Korea would always remain the North's "most hostile enemy state."
He mocked South Korea as "world-startling fools" for raising their hopes after North Korean leader Kim Jong Un's sister praised South Korean President Lee Jae Myung for his expression of regret over a recent incursion of drones into the North.
He went on to use derogatory remarks against Seoul's hopes for warmer relations.
South Korean officials had interpreted Kim's sister's remarks as a rare act of conciliation. However, Jang dismissed the interpretations and said her statement was intended as a warning.
Despite Lee's repeated overtures to normalize the ties between the two arch-rivals, North Korea has refused to return to the table for a dialogue with South Korea and the United States, which insist on Pyongyang's nuclear disarmament.
