The North Korea tested the Haeil-2 underwater strategic weapon system from April 4-7.
North Korea remained unresponsive to regular contact via a military hotline for the second day on Saturday, military officials said.
The North did not respond to the regular 9 a.m. opening call between the two sides after daily calls through the cross-border liaison line and the military hotline the previous day went unanswered, Yonhap News Agency quoted the officials as saying.
The two Koreas typically hold phone calls twice a day in the morning and in the afternoon using the joint liaison office channel and their military channel.
While the liaison office channel operates only on weekdays, the military channel also conducts calls on weekends.
“Regular calls aren’t being made due to an unspecified reason from the North’s side,” a military official said.
“We will monitor the situation, including the possibility of a (technical) problem in the North’s line.”
The suspension comes amid heightened tensions on the Korean Peninsula in the wake of North Korea’s recent weapons tests in protest of joint military drills between South Korea and the US.
Underwater n-capable attack drone
Earlier in the day, the North’s state media reported that the country staged an underwater detonation test of its Haeil-2 nuclear-capable attack drone earlier this week, proving the weapon system’s reliability and “fatal” striking capability.
The North tested the Haeil-2 underwater strategic weapon system from April 4-7, according to Pyongyang’s official Korean Central News Agency (KCNA).
“The system will serve as an advantageous and prospective military potential of the armed forces of the DPRK essential for containing all evolving military actions of enemies, removing threats and defending the country,” Yonhap News Agency quoted the KCNA as saying.
The test drone was deployed from a port in South Hamgyong Province on Tuesday, and “correctly set off” a test warhead underwater on Friday after cruising along an “oval and eight-shaped” course simulating a distance of 1,000 km for 71 hours and six minutes, it added.
The provocation came about two weeks after the North first made public a test of its underwater attack drone Haeil on March 24.
It claimed the “secret weapon” is capable of generating a “radioactive tsunami” and stealthily attacking enemies.
On March 28, the regime unveiled its Hwasan-31 tactical nuclear warhead for the first time and claimed that it had staged an underwater detonation test of its Haeil-1 drone a day earlier.
Considering the change in the weapon’s name in the latest test, the North could have tested an improved version of the Haeil this week, observers said.
The North has recently intensified its provocative acts, such as the unveiling of the Hwasan-31 tactical nuclear warhead and the launch of cruise missiles from a submarine.
Observers said the North is likely to bolster its weapons tests on key anniversaries this month, namely the 111th birthday of the country’s late founder Kim Il-sung on April 15.