North Korea fired at least 17 missiles into the sea on Wednesday, including one that landed less than 60 kilometres off South Korea's coast, which the South's President Yoon Suk-yeol described as "territorial encroachment" by Pyongyang.
It was the first time a ballistic missile had landed near the South's waters since the peninsula was divided, and the most missiles fired by the North in a single day. South Korea issued rare air raid warnings and launched its own missiles in response as tensions spiralled in the region.
South Korean warplanes in response fired three air-to-ground missiles into the sea north across the Northern Limit Line (NLL), a disputed inter-Korean maritime border, the South's military said. An official said the weapons used included an AGM-84H/K SLAM-ER, which is a U.S.-made precision attack weapon that can fly for up to 270 kilometres with a 360-kilogram warhead.
The South's launches came after Yoon's office vowed a "swift and firm response" so North Korea "pays the price for provocation."
"North Korea's provocation today was an effective act of territorial encroachment by a missile intruding the NLL for the first time since [the two Koreas'] division," Yoon's office said.
Evacuations on South Korean island
The North Korean weapon was one of three short-range ballistic missiles fired from the North Korean coastal area of Wonsan into the sea, South Korea's Joint Chiefs of Staff (JCS) said. The JCS later said as many as 14 other missiles of various types had been fired from North Korea's east and west coasts.
The JCS said at least one of the missiles landed 26 kilometres south of the NLL, 57 kilometres from the South Korean city of Sokcho, on the east coast, and 167 kilometres from the island of Ulleung, where air raid warnings were issued.
"We heard the siren at around 8:55 a.m. and all of us in the building went down to the evacuation place in the basement," an Ulleung county official told Reuters. "We stayed there until we came upstairs at around 9:15 after hearing that the projectile fell into the high seas."
A resident on the southern part of the island said they received no warnings.
The North also fired more than 100 rounds of artillery from its east coast into a military buffer zone established in a military agreement with the South, South Korea's military said.
The firing violates the 2018 agreement, the JCS said.
Hours later, North Korea fired six additional missiles off its east and west coasts, South Korea's military said.
The Japan Coast Guard also said North Korea fired at least one likely short-range ballistic missile eastward, which flew at an "extremely low altitude below 50 kilometres at maximum."
Angered by joint drills
Nuclear-armed North Korea has tested a record number of missiles this year, and officials in Seoul and Washington say the North has completed technical preparations to conduct a nuclear weapon test for the first time since 2017.
The launches came just hours after Pyongyang demanded that the United States and South Korea stop large-scale military exercises, saying such "military rashness and provocation can be no longer tolerated."
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The United States and South Korea began one of their largest combined military air drills on Monday. Dubbed Vigilant Storm, the exercises involve hundreds of warplanes from both sides staging mock attacks 24 hours a day.
North Korea had said that a recent flurry of launches were in response to allied drills.
Pak Jong Chon, secretary of the Central Committee of North Korea's ruling Workers' Party, said in a statement on Wednesday that the number of warplanes involved in Vigilant Storm proved the exercise was "aggressive and provocative" and specifically targeted North Korea.
"The hostile forces' inordinate moves for military confrontation have created a grave situation on the Korean peninsula," Pak said in a statement carried by state news agency KCNA.
On Tuesday in Washington, U.S. State Department spokesperson Ned Price said that the drills were "purely defensive in nature" and that the United States had made clear to North Korea that it harboured no hostile intent toward the country.
U.S., Japan condemn tests
In a phone call with U.S. Secretary of State Antony Blinken, South Korean Foreign Minister Park Jin called the North Korean missile launch "unprecedented" and a "grave act of military provocation." The two officials condemned the launch and agreed to co-operate against North Korean threats, Park's office said in a statement.
South Korea's Ministry of Land, Infrastructure and Transport said that because of the launches, some air routes over the sea between North Korea and Japan would be closed until Thursday morning.
Japanese Defence Minister Yasukazu Hamada condemned the launches as well, saying that North Korea's actions threaten the peace and stability of Japan, the wider region, as well as the broader international community, and are utterly unacceptable.
"North Korea has been repeatedly launching missiles at an unprecedented rate, in new ways that we have not seen before," he said.
