ALBAWABA- A U.S. Navy submarine torpedoed and sank the Iranian frigate IRIS Dena in the Indian Ocean off the southern coast of Sri Lanka on Wednesday, in what officials described as the deadliest attack on Iran’s naval forces since the February 28 bombing of a girls’ school in Tehran.
U.S. Defense Secretary Pete Hegseth confirmed the strike, saying the submarine hit the vessel about 40 nautical miles south of Galle during heightened hostilities with Tehran.
The Moudge-class warship, returning from India’s MILAN 2026 multinational naval exercises, sent a distress call early Wednesday with approximately 180 crew members aboard before sinking.
Sri Lankan forces rescued 32 injured sailors who were taken to hospitals in Galle, and multiple bodies have been recovered, but more than 100 crew members remain missing as search and rescue operations continue.
❗️ ‘At Least 80 Dead in US Strike on Iranian Frigate’ – Reuters Citing 🇱🇰Deputy FM
— RT_India (@RT_India_news) March 4, 2026
The IRIS Dena was heading back to Iran from MILAN naval exercises in India.
📹: US Dept of War https://t.co/CmngquBZnY pic.twitter.com/r58KE1zsUq
Iranian officials condemned the strike as a grave act of aggression and vowed retaliation, though no immediate response was reported. The attack represents a significant escalation in the broader U.S.–Iran conflict following joint U.S.–Israeli airstrikes that killed Supreme Leader Ali Khamenei and more than 40 senior officials in Tehran. Those strikes ignited Operation True Promise 4, an Iranian campaign of missile and drone attacks on U.S. bases, Gulf infrastructure, and allied targets.
The sinking of the Dena underscores the widening scope of the conflict, which has already disrupted energy markets and triggered a surge in global oil prices.
The United Nations Security Council has held emergency discussions as tensions spread beyond the Middle East, raising fears of a prolonged and broader confrontation. The loss of the Iranian warship marks a dramatic intensification of naval hostilities and could further destabilize the region.
