(ATTN: UPDATES with more info in paras 3-10; ADDS photo)
SEOUL, July 9 (Yonhap) -- North Korea fired a submarine-launched ballistic missile (SLBM) off its east coast on Saturday, but the missile failed in its initial flight stage, South Korea's Joint Chiefs of Staff (JCS) said.
The missile was fired from waters southeast of the coastal port city of Sinpo, South Hamgyong Province, at around 11:30 a.m., according to the military.
"The SLBM was ejected from the submarine normally, but (we) estimate the initial flight was unsuccessful," the JCS said in a brief press release.
"Our military strongly denounces such provocative acts by North Korea," the JCS noted.
North Korea's ballistic missile launches are direct violations of United Nations Security Council resolutions, including its Musudan missile launches on June 22 and the latest launch, the military said.
Military sources said the latest SLBM appears to have exploded at an altitude of some 10 kilometers after being fired from a submerged 2,000-ton Sinpo-class submarine.
The missile flew only a few kilometers before the presumed explosion, they said.
South Korea's military said that North Korea has achieved progress in the initial undersea ejection stage of its SLBM technology.
The North is probably in the flight test stage of its SLBM before moving onto the final test phase that will require the missile to hit targets, the sources said.
The North may be ready to deploy its SLBMs for service in about three years, according to the military.
The latest launch came less than three months after the communist country's previous SLBM test fire ended in failure.
The sea-based missile, launched on April 23 from the East Sea, broke into several pieces in mid-flight after flying some 30 kilometers, military officials have said.
The Saturday launch is Pyonyang's latest show of force and comes a day after Seoul and Washington's announcement to deploy a Terminal High Altitude Area Defense battery, a high-tech U.S. air defense system, in Korea to counter the North's nuclear and ballistic missile threats.
Also, earlier in the week the U.S. Treasury Department blacklisted North Korean leader Kim Jong-un and 22 other officials and state entities for human rights violations. The move marks the first time the United States has imposed direct sanctions on the North's leadership, and is seen as a warning that it will hold those responsible for abuses.
The North has angrily protested the U.S. decision, saying the move constitutes crossing a "red line."
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