Amid high tensions, North Korea fired another short-range ballistic missile into the sea off its east coast on Friday. South Korea's National Security Council (NSC) condemned the act of escalating tensions and called it a violation of the 2018 bilateral military pact that bans "hostile acts" in the border area.
According to reports, South Korea also took guard by deploying fighter jets when about 10 North Korean military aircraft flew close to their border. As per South Korea's military, North Korea had fired around 170 rounds of artillery into the "sea buffer zones" of its east and west coast.
South Korea's Joint Chiefs of Staff (JCS) issued a warning to North Korea and urged to stop provocations and escalating tensions.
South Korean President Yoon Suk-yeol told reporters that Pyongyang has been "indiscriminately carrying out provocations," vowing to devise "watertight countermeasures".
Meanwhile, North Korea's military issued a statement saying that it took "strong military countermeasures," over South Korea's artillery fire on Thursday. South Korea's NSC said that the firing was a "regular, legitimate" exercise.
The incidents came after KCNA said leader Kim Jong Un had overseen the launch of two long-range strategic cruise missiles on Wednesday to confirm the reliability of nuclear-capable weapons deployed to military units.
The unprecedented frequency of North Korea's missile launches has raised concerns it may be preparing to resume testing of nuclear bombs for the first time since 2017.
South Korea's JCS said the missile launched at 1:49 a.m. on Friday (1449 Thursday GMT) from the Sunan area near North Korea's capital, Pyongyang, and flew about 700 km (435 miles) to an altitude of 50 km at a speed of Mach 6. Japan's coast guard also reported the launch, which was at least the 41st ballistic missile test by the North this year.
The JCS said the aircraft incident occurred for about two hours from 2230 on Thursday (1130 GMT), during which about 10 North Korean warplanes flew as close as 12 km (7 miles) north of the sea border and 25 km (15 miles) north of the Military Demarcation Line.
South Korea's military will hold its annual Hoguk defence drills starting next week, including field training simulated to counter the North's nuclear and missile threats, it added.
The latest ballistic missile launches including the one that flew over Japan last week, were called a show of force against joint South Korean and US military drills by North Korea.