US Submarine Sinks Iranian Warship IRIS Dena in Indian Ocean; Over 100 Sailors Feared Dead
News Desk: In a major escalation of the ongoing US-Iran confrontation, an Iranian naval warship, IRIS Dena, was sunk by a US submarine in the Indian Ocean, leaving more than 100 sailors feared dead, according to international media reports.
Authorities in Sri Lanka said naval teams have so far recovered 87 bodies of Iranian sailors from waters off the country’s southern coast following the strike. Search operations are continuing as dozens of crew members remain missing.
Officials reported that 61 sailors are still unaccounted for, raising concerns that the death toll may climb further. Meanwhile, 32 survivors have been rescued and are receiving treatment at a hospital in the coastal city of Galle.
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Earlier in the day, US Defence Secretary Pete Hegseth confirmed that the Iranian vessel was torpedoed in international waters. Speaking at the Pentagon, he said the attack demonstrated the reach of American naval power.
“An American submarine sank an Iranian warship that thought it was safe in international waters,” Hegseth said, referring to the vessel identified as the frigate IRIS Dena.
“Instead, it was sunk by a torpedo. Quiet death,” he added.
The IRIS Dena, a Moudge-class frigate operated by the Iranian Navy, had recently taken part in MILAN 2026, a multinational naval exercise held in the Bay of Bengal from February 18 to 25. The vessel was reportedly returning to Iran from an eastern Indian port after participating in the exercise when it was struck.
The warship had also participated in the 2024 edition of the same multinational exercise, highlighting Iran’s previous naval engagement in regional maritime drills.
In an unusual step, the US Department of Defense released black-and-white footage that appeared to show a submarine periscope view followed by a distant explosion at sea. Analysts say the rare disclosure reflects how modern conflicts are increasingly fought not only on the battlefield but also in the information sphere.
The Pentagon has indicated that weakening Iran’s naval capabilities forms a key objective of the broader US-Israeli military campaign against Tehran.
The sinking of IRIS Dena is being seen as a significant escalation in the maritime dimension of the conflict and raises fears that tensions could spread further across strategic waters of the Indian Ocean, a vital corridor for global trade and energy routes.
