North Korea fired four short-range ballistic missiles (SRBM) toward the Yellow Sea on Saturday, the South Korean military said.
The Joint Chiefs of Staff (JCS) said it detected the launches from Tongrim County in North Pyongyan Province between around 11:32 a.m. and 11:59 a.m., Yonhap news agency reported.
The missiles flew about 130 km at an apogee of 20 km with a top speed of Mach 5, it added.
The North Korea's latest "provocation" came on the last day of the extended large-scale combined air drills of the South Korea and the US.
On Saturday two B-1B strategic bombers joined the Vigilant Storm exercise alongside four South Korean F-35A stealth fighter jets and four US F-16 fighters, the JCS said.
It marked the first time the B-1B Lancer has been deployed to the Korean Peninsula since 2017, in a demonstration of Washington's firm commitment to extended deterrence for South Korea and the allies' combined defense posture, JCS added.
The North has launched a barrage of ballistic missiles into the East Sea and the Yellow Sea, including an intercontinental ballistic missile (ICBM), apparently in protest against the Vigilant Storm.