North Korea Says It Fired Two Submarine-Launched Cruise Missiles, Shows Hero Kim Kun Ok Submarine at Sea

North Korea said on October 15 that it had test-fired two types of what it called "submarine-launched strategic cruise missiles" in the sea off its east coast the previous day, in launches that South Korea's military said it tracked from before liftoff to the end of flight. State news agency KCNA, which carried the announcement, did not identify the submarine involved or disclose the missiles' ranges or flight paths.

According to KCNA, the October 14 tests were intended to examine the reliability of the country's war deterrent and the readiness of its combat systems, and to improve the navy's ability to carry out what Pyongyang terms strategic missions. The agency said the launches had no adverse impact on the security of neighboring countries. KCNA identified one of the missiles as a Pulhwasal-3-31, the same type of cruise missile it said had been fired from land the previous week.

South Korea's Joint Chiefs of Staff said it detected and tracked the launches before launch, in flight and through to the end of flight, Stars and Stripes reported. "We understand that one type [of missile] was launched from a vertical launch tube, while the other was launched from a torpedo tube," a JCS spokesperson said, declining to give further details. The South Korean military assessed that the launches came from a submarine but did not publicly identify the vessel, according to The War Zone.

KCNA released a single photograph of the Hero Kim Kun Ok submarine underway. The War Zone said this appears to be the first publicized at-sea appearance of the boat, which Pyongyang unveiled in September 2023 and described as its first "tactical nuclear attack submarine." The outlet cautioned that the submarine may not have been the launch platform, noting that North Korea has long used underwater test platforms while releasing images of real submarines. If Hero Kim Kun Ok did fire the missiles, The War Zone said, the launches would be its first confirmed weapons trials.

Hero Kim Kun Ok is a heavily modified derivative of the Cold War-era Romeo-class diesel-electric submarine, a 3,000-ton-class boat, according to The War Zone. Earlier imagery shows 10 missile launch tubes in a raised "turtle back" structure aft of the sail, the forward four larger than the rear six, in addition to torpedo tubes. The older 8.24 Yongung, from which North Korea fired cruise missiles in a publicized test in March 2023, is a 2,000-ton-class submarine with one or two vertical tubes, The War Zone said.

GlobalMilitary.net data on North Korea's submarine fleet lists 20 Romeo-type (Type-033) diesel-electric submarines, one Sinpo-class boat, the 8.24 Yongung with hull number 824, and Hero Kim Kun Ok, hull number 841, recorded as still fitting out. The same inventory counts 56 smaller Sang-O and Yono coastal submarines in active service.

The October 14 launches appear to be the first publicly reported submarine-launched cruise missile test since January 28, 2024, when North Korea fired two Pulhwasal-3-31 missiles that KCNA said flew for 7,421 and 7,445 seconds before striking an island target, according to Stars and Stripes. North Korea is also pursuing a separate nuclear-powered submarine, which it showed under construction in March 2025, The War Zone reported.

The test follows a run of launches this month. On October 3, North Korea fired a ballistic missile it described as hypersonic, and on October 12 it launched two ballistic missiles toward the sea off its east coast from near Pyongyang, which South Korea's Joint Chiefs of Staff said flew more than 560 miles (about 900 km), Stars and Stripes reported.

The War Zone said a submarine-launched ballistic missile test from Hero Kim Kun Ok would be a likely milestone toward North Korea fielding a sea-based nuclear deterrent.