South Korean President Yoon Suk-yeol told reporters that Pyongyang has been "indiscriminately carrying out provocations", vowing to devise "watertight countermeasures". North Korea's military issued a statement via state media KCNA early on Friday saying that it took "strong military countermeasures", over artillery fire by South Korea on Thursday. 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. It said the South Korean air force "conducted an emergency sortie with its superior air force, including the F-35A". "The KPA sends a stern warning to the South Korean military inciting military tension in the frontline area with reckless action," its spokesman said, according to KCNA.

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