(ATTN: UPDATES with more details in 9th para)
By Song Sang-ho, Kang Yoon-seung and Chae Yun-hwan
SEOUL, Jan. 17 (Yonhap) -- North Korea fired two suspected short-range ballistic missiles eastward from an airfield in Pyongyang on Monday, South Korea's military said, in the recalcitrant regime's fourth show of force this year.
The Joint Chiefs of Staff (JCS) said it detected the projectiles fired from the Sunan airport at 8:50 a.m. and 8:54 a.m., respectively, and that they flew about 380 kilometers at an altitude of 42 km.
The missiles traveled at a top speed of Mach 5, five times the speed of sound, according to an informed source.
The North's latest weapons test appears aimed at enhancing its ability to consecutively launch missiles with increased accuracy, a JCS official said on condition of anonymity.
"For additional information, including intentions behind the North's recent series of short-range ballistic missile launches, the intelligence authorities of South Korea and the United States are conducting a detailed analysis," the official told reporters.
The official added that South Korea's military possesses capabilities to both detect and intercept the projectiles in question, and has continuously been reinforcing its system to respond to them.
As to the type of the missile launched Monday, the JCS is looking into "various possibilities," including the projectile being the KN-23 modeled after Russia's Iskander mobile ballistic missile, according to the official.
The KN-23 missile is known to employ a so-called pull-up maneuver -- a technique designed to avoid interception and thus complicate South Korea's missile defense efforts.
Some observers raised the possibility that Monday's missile could be the North Korean version of the U.S.' Army Tactical Missile System (ATACMS), called the KN-24. It is also known to fly on a complicated trajectory to evade interception.
Monday's launch came just three days after the North launched two suspected short-range ballistic missiles into the East Sea that it later claimed to be guided missiles fired by a railway-borne regiment during a firing drill.
Soon after the latest launch, South Korea's presidential National Security Council held an emergency meeting and called the North's continued weapons tests "very regrettable."
Separately, Seoul's unification ministry urged the North to restart dialogue rather than missile launches for the goal of peace and stability on the Korean Peninsula.
The U.S. Indo-Pacific Command said it was aware of the "ballistic missile launches" but assessed the latest event "does not pose an immediate threat to U.S. personnel or territory or to our allies."
"These missile launches highlight the destabilizing impact of the DPRK's illicit weapons program," it said in a press release, referring to the North's official name, Democratic People's Republic of Korea. "The U.S. commitment to the defense of the Republic of Korea and Japan remains ironclad."
Monday's firing from Pyongyang appears to underscore the North's evolving capabilities to launch missiles from various platforms, including trains, subsurface assets and land-based facilities.
Last week, the North warned of a "stronger and certain reaction" to the United States' recent imposition of fresh sanctions on six North Koreans involved in the regime's weapons of mass destruction and ballistic missile programs.
The warning was followed by the North's test-firing of two projectiles from a train-based platform Friday.
The North also test-fired its self-proclaimed hypersonic missile on Jan. 5 and on Tuesday last week, ratcheting up tensions amid an impasse in nuclear negotiations with the U.S.
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