North Korea fired at least one unidentified ballistic missile Monday, South Korea’s military said, the latest in its flurry of weapons tests in recent weeks. “North Korea fires an unidentified ballistic missile towards the East Sea,” Seoul’s Joint Chiefs of Staff said, referring to the body of water also known as the Sea of Japan. The launch comes just days after Seoul and Washington wrapped up their largest joint military drills in five years Thursday. Pyongyang views all such exercises as rehearsals for invasion and on Friday claimed the recent drills, dubbed Freedom Shield, were practice for “occupying” North Korea. Pyongyang carried out military drills of its own in response, including test-firing a new nuclear-capable underwater drone and conducting its second intercontinental ballistic missile launch this year. After a record-breaking year of weapons tests and growing nuclear threats from Pyongyang in 2022, Seoul and Washington have ramped up security cooperation. North Korea last year declared itself an “irreversible” nuclear power and leader Kim Jong Un recently called for an “exponential” increase in weapons production, including tactical nuclear weapons.