Galle, Sri Lanka / Washington DC — An American submarine has sunk an Iranian warship in the Indian Ocean off the coast of Sri Lanka, US Defence Secretary Pete Hegseth confirmed on Wednesday, marking the first US sinking of an enemy vessel by torpedo since World War II.
The submarine used an MK-48 heavyweight torpedo to strike the 1,500-ton Moudge-class frigate IRIS Dena, which had recently operated in the Bay of Bengal for exercises. The vessel went down approximately 40 kilometres south of Galle, just outside Sri Lanka’s territorial waters.
The sinking extends Operation Epic Fury — the joint US-Israeli military campaign that killed Supreme Leader Ali Khamenei and seven senior Iranian defence officials last Saturday — into the Indo-Pacific for the first time.
Pentagon Confirmation
Speaking at a Pentagon press briefing, Hegseth confirmed the submarine strike.
“In the Indian Ocean, an American submarine sank an Iranian warship that thought it was safe in international waters. Instead, it was sunk by a torpedo — quiet death — the first sinking of an enemy ship by a torpedo since World War II,” he said.
“Like in that war, back when we were still the War Department, we are fighting to win,” Hegseth added, opening the briefing by stating “America is winning.”
Hegseth also confirmed the US had sunk Iran’s “prize ship” — a vessel named the Soleimani, after the former Iranian general Qasem Soleimani who was killed by US forces during Trump’s first term. “I guess POTUS got him twice,” Hegseth said.
US Navy’s Stated Objective — Sink the Entire Iranian Navy
CENTCOM commander Admiral Brad Cooper said the US is focused on “sinking the Iranian Navy — the entire Navy.”
“Today there is not a single Iranian ship underway in the Arabian Gulf, Strait of Hormuz or the Gulf of Oman, and we will not stop,” Cooper said in a video posted on X.
US officials confirmed the destruction of more than 20 Iranian naval vessels in total, including the IRIS Dena.
Casualties and Conflicting Reports
Sri Lanka’s deputy foreign minister told local television that at least 80 people were killed in the strike. Sri Lankan authorities said they had rescued 32 people from the ship and recovered several bodies from the sea.
Around 140 people remain missing, according to Sri Lanka’s Defence Ministry Secretary Air Vice Marshal Sampath Thuiyakontha.
Sri Lankan naval spokesman Buddhika Sampath confirmed the rescue operation was conducted under international maritime obligations.
“Though it was beyond our waters, it was within our search and rescue region. So we were obliged to respond as per international obligations,” he said.
Police in Galle stepped up security around the hospital where injured Iranian sailors were being treated. Sri Lanka’s navy and air force said they would not release footage of the rescue operation as it involved the military of another country.
The IRIS Dena
The IRIS Dena is a Moudge-class frigate belonging to Iran’s southern fleet, named after Mount Dena. It is among Iran’s most modern and capable surface combatants, armed with heavy guns, surface-to-air missiles, anti-ship missiles and torpedoes, with a crew of 180 personnel.
The vessel had issued a distress call at dawn before going down, according to Sri Lankan officials.
Broader Context
Hegseth said Iran’s senior leaders are dead and that the governing council that might have selected a successor is “dead, missing, or in bunkers,” with senior generals and mid-level officers unable to communicate.
The warship’s sinking comes as the US and Israel conduct air strikes on Iran for a fifth consecutive day. Tehran has responded with drone and missile attacks on Israel and US-linked assets in Gulf countries, causing multiple fatalities, Fox News reports
Senior Iranian officials have already warned of retaliation against US military bases across the Middle East. The extension of hostilities into key Indian Ocean shipping lanes raises further concerns for global energy markets and trade routes.
Search operations for the remaining crew continue as international reaction builds.
This is a developing story. Updates will follow as more facts are confirmed.
