A faulty ballistic missile launched by South Korea crashed and blew up during a live-fire drill with the US on Wednesday.
The launch was in response to North Korea's launch of a ballistic missile over Japan for the first time in five years on Tuesday.
The explosion on Wednesday in the South Korean coastal city of Gangneung caused panic among residents who were uneasy over weapons tests across the border.
With the military and government officials giving no explanation for the explosion for many hours, concerns of a North Korean attack grew.
South Korea’s Joint Chiefs of Staff said no injuries have been reported from the explosion, which involved a short-range Hyumoo-2 missile that crashed inside an air force base in the outskirts of the city.
It said the crash did not affect any civilian facilities.
During the same drill, the US military launched four of its own missiles that are part of the Army Tactical Missile System and South Korea fired another Hyumoo-2 successfully.
The home-grown missile is key to South Korea’s pre-emptive and retaliatory strike strategies against the North and is a version of a Russian-designed Iskander missile, which is also possessed by the North.
Kwon Seong-dong, a ruling party politician representing Gangneung, wrote on Facebook that a “weapons system operated by our bloodlike taxpayer money ended up threatening our own people” and called for the military to thoroughly investigate the missile failure.
He also criticised the military for not issuing a notice about the crash while maintaining a media embargo on the joint drills.
“It was an irresponsible response,” Mr Kwon wrote. “They don’t even have an official press release yet.”
South Korea’s military acknowledged the missile malfunction hours after internet users raised alarm about the blast and posted social media videos showing an orange ball of flames emerging from an area they described as near the air force base.
It said it was investigating what caused the “abnormal flight” of the missile.
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Officials at Gangneung’s fire department and city hall said emergency workers were sent to the air force base and a nearby army base in response to calls about a possible explosion but were sent back by military officials.
The US and South Korean militaries are conducting the joint exercises to show their ability to deter a North Korean attack on the South. In addition to missile launches, they involved bombing runs by F-15 jets.
North Korea’s successful launch of a nuclear-capable ballistic missile hours before the drills was the country’s most provocative weapons demonstration since 2017 and was its fifth round of weapons tests in 10 days.
That missile has a range capable of striking the US territory of Guam, which is home to one of the largest military facilities maintained by the US in Asia. North Korea in 2017 also tested missiles capable of hitting the continental US.
40 missile launches by North
North Korea has fired nearly 40 ballistic missiles over about 20 launches this year, exploiting Russia’s war on Ukraine and the resulting deep divide in the UN Security Council to accelerate its arms development without risking further sanctions.
Its aim is to develop a fully fledged nuclear arsenal capable of reaching the US mainland and its allies while gaining recognition as a nuclear state and wresting concessions from those countries.
The US, Britain, France, Albania, Norway and Ireland called for an emergency meeting of the UN Security Council over the latest North Korean launch. Diplomats said it is likely to be held on Wednesday, but it is not certain whether it will be an open or closed session.