(ATTN: UPDATES with more details in paras 5-8)
By Song Sang-ho
SEOUL, Jan. 11 (Yonhap) -- North Korea's ballistic missile launched Tuesday flew at a top speed of Mach 10, South Korea's military said, taking note of "improvement" compared with what it claimed to be a hypersonic missile test six days ago.
The Joint Chiefs of Staff (JCS) said the North fired the missile from its northern province of Jagang into the East Sea, and that it flew more than 700 kilometers at a maximum altitude of 60 km and at a top speed of Mach 10, 10 times the speed of sound.
The launch was detected at 7:27 a.m, the JCS said. It followed the test-firing of the North's self-proclaimed hypersonic missile, which the JCS said traveled less than 700 km at a top speed of Mach 6.
"We assess that it has improved compared with the ballistic missile launched on Jan. 5," the JCS said in a text message, calling the regime's continued launches of ballistic missiles a "clear" violation of U.N. Security Council resolutions.
The resolutions prohibit the North from conducting any launches using ballistic missile technology.
The JCS' statement drew a contrast from its earlier downplaying of the North's hypersonic missile claims as "exaggeration" and its assessment that the North has yet to secure technologies for the high-tech weapon.
Experts, however, pointed out the speed of Mach 10 is not a definitive element for the categorization of hypersonic missiles, as ordinary medium-range ones typically fly at Mach 9 to 10 during boost phases after liftoff.
"For more details, South Korea and the U.S. need a detailed analysis," a JCS official said on condition of anonymity.
The South Korean military also urged the North to immediately halt its missile launches.
"(The launches) pose a significant threat to peace and security not only on the Korean Peninsula but also in the world, and are not helpful for the reduction of military tensions," it said.
The U.S. Indo-Pacific Command characterized the North's latest projectile as a "ballistic missile," which it said highlights the "destabilizing impact" of the North's illicit weapons program.
The South's presidential National Security Council soon convened an emergency meeting and expressed "strong regret."
The latest launch came as the UN Security Council held a closed-door session on Pyongyang's missile launch last week.
Shortly before the session, the U.S. and five other countries issued a joint statement calling on the North to refrain from "destabilizing" actions, abandon its ballistic missile programs and engage in "meaningful" dialogue toward denuclearization.
South Korea, meanwhile, voiced regret over another missile launch by the North and called on it to return to the dialogue table.
The Ministry of Unification reiterated improving inter-Korean relations to an "irrevocable level" is crucial to fundamentally resolving concerns stemming from such missile launches.
"North Korea should choose cooperation for peace over acts that go against efforts to build peace on the Korean Peninsula, such as the latest missile launches, at this critical moment to stabilize the political situation surrounding the peninsula," a unification ministry official told reporters.
Pyongyang's latest saber-rattling came as the North unveiled its ambitious push to develop an array of new formidable weapons during the eighth congress of the ruling Workers' Party a year ago.
During the congress, the North catalogued "important strategic tasks," such as developing tactical nuclear weapons, a hypersonic gliding flight warhead, a nuclear-powered submarine and a reconnaissance satellite, according to its state media.
At the close of the ruling party's Central Committee plenary late last month, North Korean leader Kim Jong-un redoubled calls to bolster defense capabilities "without a moment's delay," pointing to unstable international security conditions.
"(The latest launches) are an expression of the North's resolve to forge ahead with the missile activities in line with an institutionalized defense plan irrespective of the external environment," Park Won-gon, a professor of North Korea studies at Ewha Womans University, said.
The North's missile launch handed yet another dispiriting setback to the South's steadfast drive to resume nuclear diplomacy with the recalcitrant regime.
Nuclear negotiations between Washington and Pyongyang have been stalled since the no-deal Hanoi summit between the two countries in February 2019.
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