North Korea fired a short-range ballistic missile on ​Thursday towards the sea off the peninsula’s eastern coast, South Korea’s ‌military said, the first such launch in more than 40 days after a series of weapons tests earlier this year.

The launch comes ahead of joint South Korean-US ​military drills expected this month.

Washington and Seoul say the exercises ​strengthen their defence capabilities and deterrence against North Korean nuclear ⁠and missile threats. Pyongyang regularly denounces them as preparations for an ​invasion.

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The South Korean military said it detected the missile launched from North ​Korea’s eastern coastal Wonsan area around 5pm (0800 GMT).

South Korea’s presidential office said it held an emergency security meeting, and condemned the launch as a provocative act ​that violates United Nations Security Council (UNSC) resolutions.

The missile test could be ​related to recent criticism by Kim Yo Jong, the powerful sister of North Korean ‌leader ⁠Kim Jong Un, of Japan’s firing of Tomahawk missiles, said Lim Eul-chul, a professor at Kyungnam University’s Institute for Far Eastern Studies.

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North Korea has launched a series of tests this year, including short-range ballistic missiles, ​artillery rockets and ​other tactical weapons.

The ⁠most recent confirmed weapons test, in late June, involved an upgraded 240-mm multiple-launch rocket system, tactical ballistic ​missiles and a 155-mm self-propelled howitzer, North Korean state ​media KCNA ⁠said.

The South Korean military said that it had heightened its alert for further firings and was sharing information with the United States and ⁠Japan.

Japan’s ​government also said on Thursday that Pyongyang had ​launched what could be a ballistic missile.