UPDATE 12-North Korea fires 23 missiles, one landing off South Korean coast for first time

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One missile lands south of disputed inter-Korean maritime border

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Air raid warning issued on S.Korean island

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S.Korea president vows N.Korea will 'pay the price'

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N.Korea calls allied military drills 'provocative'

(Adds White House national security spokesperson)

By Josh Smith and Soo-hyang Choi

SEOUL, Nov 2 (Reuters) - North Korea fired at least 23 missiles into the sea on Wednesday, including one that landed less than 60 km (40 miles) off South Korea's coast, which South Korean President Yoon Suk-yeol described as "territorial encroachment" and Washington denounced as "reckless".

It was the first time a ballistic missile had landed near the South's waters since the peninsula was divided in 1945, 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.

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".

In Washington, White House national security spokesperson John Kirby called the North Korean launches "reckless" and said the United States would make sure it had the military capabilities in place to defend its treaty allies South Korea and Japan.

The missile landed outside South Korea's territorial waters, but south of the Northern Limit Line (NLL), a disputed inter-Korean maritime border.

South Korean warplanes fired three air-to-ground missiles into the sea north across the NLL in response, the South's military said. An official said the weapons used included an AGM-84H/K SLAM-ER, which is a U.S.-made "stand-off" precision attack weapon that can fly for up to 270 km (170 miles) with a 360-kg (800-lb) warhead.

The South's launches came after Yoon's office vowed a "swift and firm response".

"President Yoon Suk-yeol noted 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," his office said.

When asked whether the missile was flying towards the South's territory and should have been intercepted, a senior presidential official said, "Strictly speaking, it did not land in our territory but in the Exclusive Economic Zone under our jurisdiction, therefore it was not subject to interception".

North Korea has continuously been launching missiles over the past year in violation of multiple U.N. Security Council resolutions, U.S. Ambassador to the United Nations Linda Thomas-Greenfield said.