TOKYO, January 19. /TASS/. North Korea tested its Haeil-5-23 nuclear-capable unmanned underwater attack weapon in response to major joint drills by the United States, Japan and South Korea, the Korean Central News Agency (KCNA) said on Friday.

"Joint maritime exercises were staged again in the waters off Jeju Island for three days from Jan. 15 with the involvement of the US nuclear carrier Carl Vinson and Aegis cruiser Princeton and warships of the Japanese maritime "Self-Defense Force" and the ROK navy," KCNA said. "In response to it, the Underwater Weapon System Institute under the DPRK Academy of Defence Science conducted an important test of its underwater nuclear weapon system 'Haeil-5-23' under development in the East Sea [Sea of Japan] of Korea."

North Korea’s underwater nuke-based countering posture "is being further rounded off and its various maritime and underwater responsive actions will continue to deter the hostile military maneuvers of the navies of the US and its allies," the report says.

On March 23, 2023, North Korea announced it had tested a nuclear-capable robotic submersible, which can cause a ‘super-powerful radioactive tsunami’ when exploding.