SEOUL, South Korea (AP) - A ballistic missile fired from a North Korean submarine on Wednesday flew about 500 kilometers (310 miles), the longest flight ever by the North for such a weapon, Seoul officials said, and range that can place all of South Korea, and possibly parts of Japan, within its striking distance.
North Korea already has a variety of land-based missiles that can strike South Korea and Japan, including U.S. military bases in those countries. But the North acquiring reliable submarine-launched missiles is a worrying development because they are harder to detect before liftoff.
South Korea's military condemned the launch as an "armed protest" against the start of annual South Korean-U.S. military drills, but they acknowledged that it showed an "improvement" in ability over previous similar missile tests.
"North Korea's nuclear and missile threats are not imaginary threats any longer, but they're now becoming real threats," South Korean President Park Geun-hye said of the launch. "Those threats are coming closer each moment."
The missile, fired from a submarine off the eastern North Korean coastal town of Sinpo, reached into Japan's air defense identification zone, according to Seoul and Tokyo officials. The U.S. Strategic Command said it tracked the North Korean submarine launch of the presumed KN-11 missile into the Sea of Japan.
The 500-kilometer distance is longer than ones recorded by other submarine-launched missiles fired by North Korea, and puts most of South Korea within its range if it is fired near the border.
Missiles of such capability could also potentially strike parts of Japan, including U.S. military bases on the island of Okinawa, considering the operational range of North Korea's Sinpo-class submarines, which could move close to 1,000 kilometers (620 miles) underwater at a time, said analyst Kim Dong-yub at Seoul's Institute for Far Eastern Studies.
North Korea fired two missiles from submarines earlier this year, but South Korean defense officials believe they exploded in midair after flying less than 30 kilometers (18 miles).
The launch was the latest in a series of missile, rocket and other weapon tests this year by North Korea, which is openly pushing to acquire a reliable weapon capable striking targets as far away as the continental U.S.
In June, North Korea, after a string of failures, sent a midrange ballistic missile more than 1,400 kilometers (870 miles) high. Analysts say the high-altitude flight meant North Korea had made progress in its push to be able to strike U.S. forces throughout the region.
Many outside experts say the North doesn't yet have a functioning long-range nuclear missile capable of reaching the continental U.S., but they acknowledge that the North has been making steady progress on its weapons programs and could one day acquire such a weapon. Some civilian experts have said they believe the North already has the technology to put warheads on shorter-range missiles that can strike South Korea and Japan.
Japanese Prime Minister Shinzo Abe called the launch an "impermissible and outrageous act" that poses a grave threat to Japan. The U.S. Strategic Command statement said that the launch did not pose a threat to North America, but that the U.S. military "remains vigilant in the face of North Korean provocations."
The Foreign Ministry of China, the North's last major ally, called for all sides concerned to avoid taking moves that increase tensions.
South Korean defense officials believe North Korea has about 70 operational submarines and appears to be mainly imitating Russian designs to develop submarine-launched missiles.
Wednesday's launch comes two days after the U.S. and South Korea began their 12-day Ulchi Freedom Guardian exercises, prompting North Korean threats of retaliation for the military drills, which it views as an invasion rehearsal. Before the launch, North Korea warned that the joint military exercises were pushing the Korean Peninsula "to the brink of a war" and asked for an urgent meeting of the U.N. Security Council.
South Korea's Foreign Ministry warned that the North's pursuit of weapons programs would only invite more sanctions, deepen its international isolation, and eventually speed up its collapse. The South's Joint Chiefs of Staff noted that the launch violated U.N. Security Council resolutions banning any ballistic missile activities by North Korea.
The launch also comes at a time of intensified animosities between the rival Koreas over the defection of a senior North Korean diplomat in London and a U.S. plan to install a sophisticated missile defense system in South Korea.
About 28,500 U.S. troops are based in South Korea to help deter potential aggression from North Korea, a legacy of the 1950-53 Korean War, which ended with an armistice, not a peace treaty. North Korea usually responds to the regular South Korea-U.S. military drills with weapons tests and fiery warlike rhetoric.
Associated Press writers Kim Tong-hyung in Seoul and Louise Watt in Beijing contributed to this report.
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