Iranian Warship Sunk By U.S. Submarine in International Waters, First Since WW2: Hegseth

An Iranian warship in international waters was sunk overnight by a U.S. nuclear-powered submarine, one of over 20 Iranian warships including a submarine and Tehran’s so-called “prize ship” destroyed by U.S. action in recent days, Secretary of War Pete Hegseth said.

Pete Hegseth and United States Chairman of the Joint Chiefs of Staff Dan Caine gave a joint briefing on Wednesday morning, where they confirmed the earlier-reported sinking of an Iranian warship off the southern coast of Sri Lanka (Ceylon) was the work of a U.S. Navy submarine.

Publishing footage of the attack, the Department of War revealed infrared periscope video showing the ‘hot’ areas of the Iranian ship — the chimney stack and the engine seawater cooling discharge — highlighted in white. The video then clearly shows the result of a torpedo exploding directly under the stern of the ship, believed to be the Moudge class frigate Dena (above, top-right quarter, a sister ship of similar construction pictured), evidenced by the whole stern being lifted out of the sea by enormous mass of rising bubbles.

The Dena then settles back into the water, the back of the ship likely broken by the force of the impact. Supplementary stills published show the ship having gone down by the stern, its bow raised high in the air as it slipped below.

Chairman of the Joint Chiefs of Staff Caine revealed the attack had been with a Mark 48 torpedo, which has both active and passive acoustic homing. The stern of a warship, where the screws turn for propulsion, is generally the loudest area and may well have attracted the torpedo’s guidance system to explode underneath that point.

As earlier reported, the Sri Lankan government intercepted a mayday call from the warship around 0600 Colombo time (0030 London) and deployed two ships as well as aircraft to conduct a search-and-rescue mission. While figures are presently unclear or contested, it has been stated that Sri Lanka government sources placed the death toll at 80 hours after the sinking, with others missing and wounded.

As stated by Hegseth and Caine, this strike is one of several against the Iranian navy in recent days. Secretary of War Hegseth said in his statement that “The Iranian navy rests at the bottom of the Persian Gulf. Combat ineffective, decimated, destroyed, defeated, pick your adjective.”

Of the frigate destroyed south of Sri Lanka, Hegseth continued: “yesterday in the Indian Ocean… an American submarine sunk an Iranian warship that thought it was safe in international waters. Instead it was sunk by a torpedo. Quiet death”. Hegseth noted it was the first such sinking of an enemy ship by torpedo for the United States Navy since the Second World War, and indeed it is the first officially acknowleged ship kill by a submarine by any navy worldwide since the United Kingdom sunk the General Belgrano cruiser in 1982.

Given all American submarines have nuclear power plants, it also has the distinction of being only the second ship kill by a nuclear submarine ever, again since 1982.

Hegseth also referred to other actions, and stated the United States had sunk Iran’s “prize ship”, the Shahid Soleimani (above). A catamaran, the ship was built in Iran and commissioned in 2022, and was armed with anti-ship cruise missiles intended to allow Iran to dominate the Persian Gulf and Gulf of Oman. The Secretary of War said: “last night we sank their prize ship, the Soleimani. Looks like POTUS got him twice. Their navy not a factor, it is no more.”

Speaking after Hegseth, United States Chairman of the Joint Chiefs of Staff Dan Caine added: “we are destroying the Iranian Navy, degrading its capacity capability and ability to conduct operations, not just in the Central Command AOR, but as the Secretary showed in the video, around the world”.

Caine said the U.S. has so far “destroyed more than 20 Iranian naval vessels” including a submarine. He continued that the U.S. has “effectively neutralised at this point in time Iran’s major naval presence in theatre out there.

“For the first time since 1945, a United States Navy fast attack submarine has sunk an enemy combatant ship using a single Mk-48 torpedo to achieve immediate effect, sending the warship to the bottom of the sea… This is an incredible demonstration of America’s global reach. To hunt, find and kill an out-of-area deployer is something that only the United States can do at this type of scale.”