At least 101 crew members are missing and believed dead after a U.S. submarine struck the Iranian naval ship IRIS Dena near southern Sri Lanka. Another 78 sailors were injured. The attack occurred early Wednesday while the vessel was returning from an international fleet review in India.
Sri Lankan naval and air units launched a rapid rescue operation after the warship issued a distress call reporting it was struck and taking on water near Galle. Authorities confirmed that about 30 crew members were rescued and taken to hospitals in Galle. Thirty-two injured sailors received treatment at Karapitiya Teaching Hospital, with one in critical condition.
Sri Lanka’s navy continues to search for missing crew members roughly 40 nautical miles off the coast. Officials said the cause appears to be a submarine attack by United States amid ongoing global tensions.
The Sri Lankan navy and air force responded quickly to the distress call. Survivors were evacuated and received medical care. Authorities said rescue teams are still searching for missing crew members at sea. The operation highlights the human toll of the attack and the urgency of maritime rescue efforts in the region.
The IRIS Dena is a modern Moudge-class frigate in Iran’s Southern Fleet. Commissioned in 2021, it has domestically produced engines and weapons. The frigate had recently taken part in the MILAN 2026 multinational naval exercise in India before the attack.
The U.S. Department of Defense confirmed that the strike was carried out by a fast-attack submarine using a single Mk 48 torpedo. Officials described it as the first sinking of an enemy surface ship by a U.S. submarine since World War II. Infrared footage released by the Pentagon shows the torpedo hitting the vessel, causing massive damage to the stern and sinking the ship.
The attack has raised concerns about tensions in the Indian Ocean region. Sri Lankan authorities remain focused on rescue efforts, while the U.S. continues to assess the strike’s impact on Iran’s naval capabilities. This incident marks a rare and significant escalation in naval operations in the region.
