North Korea fired two short-range ballistic missiles into the East Sea in an apparent protest against the annual South Korea-U.S. military drills that began Monday.

South Korea issued a stern warning against the “foolhardy and provocative” act, stressing that the launches violated the U.N. Security Council resolutions against the North’s use of ballistic missile technology, and that Seoul and Washington were ready to counter additional provocations.

Between 6:33 a.m. and 6:41 a.m., the North fired two Scud missiles from its western port city of Nampo southwest of Pyongyang, Seoul officials said. The two missiles, which traveled at a top speed of Mach 4.3 and maximum altitude of 134 km, flew 495 km and 493 km, respectively.

“We believe the launches are a show of force against the Key Resolve and Foal Eagle drills. Our military is keeping close tabs on the North Korean military’s movements and maintaining a robust readiness posture,” Seoul’s Defense Ministry spokesman Kim Min-seok told reporters.

Given the trajectory and range of the missiles, Seoul believes the North fired Scud-C missiles. The North has Scud-B missiles with a range of 300 km, Scud-C missiles with a range of 500 km, Scud-D missiles with a range of more than 700 km, and the Scud-ER ― an upgraded version of the Scud-D missile.

Over the past month, the North has ratcheted up military tension, calling on Seoul and Washington to cancel their annual drills, which the allies argue are defensive in nature and will proceed transparently.

On Feb. 6, the North fired four KN-01 ship-to-ship missiles with a range of some 100 km. Two days later, the North launched one KN-02 missile and four KN-09 missiles that have a range of around 200 km. 

Before the missile launches on Monday morning, the General Staff of the North’s Korean People’s Army criticized Seoul and Washington for conducting the joint drills, repeating its argument that the drills are a rehearsal for a “nuclear war of invasion” against the North.

“We will never just stand by idly. We will make (South Korea and the U.S.) deeply regret (their decision to push ahead with the drills),” said an unidentified spokesperson of the General Staff in a statement carried by the North’s Korean Central News Agency.

“The only means to deal with the imperialist U.S. and its sympathizers is neither dialogue nor peace, but a baptism of fire.”

Seoul’s Defense Ministry spokesman criticized the North’s threatening rhetoric as a “very serious challenge” to the security of the Korean Peninsula.

The allied Key Resolve command post exercise will continue through next Friday. The computer simulation exercise involves some 8,600 U.S. troops and 10,000 South Korean troops. The Foal Eagle field exercise, which involves 3,700 U.S troops and 200,000 South Korean troops, will continue through April 24.

Meanwhile, Japan issued a protest against the North’s missile launches, calling them “very problematic” in terms of the safety of aircraft and vessels operating in the areas where the missiles had traveled.

By Song Sang-ho (sshluck@heraldcorp.com)