A U.S. Navy submarine executed the first American torpedo strike on an enemy warship since World War II, sending an Iranian frigate to the bottom of the Indian Ocean and demonstrating the overwhelming superiority of our naval forces under President Trump’s Operation Epic Fury.
Story Snapshot
- U.S. submarine sank Iranian frigate IRIS Dena with Mk 48 torpedo off Sri Lanka, marking first such attack since WWII
- Pentagon released periscope video showing the strike that killed approximately 80 Iranian sailors
- Attack represents escalation of Operation Epic Fury, which has already destroyed over 20 Iranian vessels
- Defense Secretary Pete Hegseth confirmed the strike as part of ongoing effort to neutralize Iran’s naval capabilities
Historic Torpedo Strike Demonstrates Naval Dominance
The U.S. Navy submarine struck the Iranian frigate IRIS Dena late Tuesday night, March 3, 2026, approximately 44 nautical miles off Galle, Sri Lanka, in international waters. Defense Secretary Pete Hegseth confirmed the attack represented the first American submarine torpedo strike on an enemy vessel since World War II. The Pentagon released infrared periscope video showing the Mk 48 torpedo’s detonation against the frigate’s stern, causing catastrophic hull damage. Joint Chiefs Chairman Gen. Dan “Razin” Caine detailed the attack involved a fast-attack submarine, likely Los Angeles-class, deploying the 650-pound warhead torpedo that buckled the Iranian vessel’s hull before it sank completely.
Iranian Frigate Was Sanctioned for Weapons Smuggling
IRIS Dena, a modern Moudge-class frigate equipped with missiles and torpedoes, had been sanctioned by the U.S. Treasury in February 2023 for supplying weapons to Russia for use in Ukraine. The vessel represented one of Iran’s most capable surface combatants, having recently participated in India’s 2026 MILAN naval exercise before departing toward the Indian Ocean. This strike followed broader U.S.-Israel operations under Operation Epic Fury that destroyed more than 20 Iranian vessels earlier in the week, targeting Iran’s ballistic missiles, air defenses, and naval infrastructure. Iran retaliated with regional missile strikes and halted shipments through the Strait of Hormuz, escalating tensions across multiple theaters.
Rescue Operations Reveal Heavy Casualties
Sri Lanka received a distress call at 5:08 a.m. Wednesday, March 4, reporting an explosion aboard the Iranian warship. The Sri Lankan Navy dispatched vessels around 6:00 a.m., rescuing between 32 and 79 crew members while recovering 87 bodies from the debris field marked by oil slicks. Casualty figures varied across reports, with approximately 80 sailors killed from a total crew estimated between 101 and 180 personnel. Sri Lankan Foreign Minister Vijitha Herath and Navy spokesman Commander Buddhika Sampath confirmed rescue operations occurred within Sri Lanka’s exclusive economic zone, though the strike happened in international waters. Iran’s embassy in Colombo claimed deliberate U.S. targeting after defensive systems were allegedly disabled, though Tehran remained publicly silent on the incident.
Operation Epic Fury Extends Beyond Middle East
The submarine strike marks a significant expansion of U.S. military operations beyond the Middle East theater into the Indian Ocean, demonstrating reach and resolve under the Trump administration’s approach to Iranian aggression. Gen. Caine announced CENTCOM would continue strikes for 24 to 48 hours, effectively neutralizing Iran’s naval presence in the region. The attack validates the effectiveness of U.S. submarine warfare capabilities and the Mk 48 ADCAP torpedo system against modern surface combatants. Defense analysts confirmed the Iranian frigate was essentially a sitting duck against American submarine technology, unable to detect or defend against the underwater threat. This precedent-setting engagement recalls only the 1982 sinking of Argentina’s General Belgrano by Britain’s HMS Conqueror during the Falklands War as a comparable modern naval torpedo attack.
The sinking of IRIS Dena sends an unmistakable message about American naval superiority and the consequences of Iranian maritime aggression. Under President Trump’s leadership, the United States demonstrates willingness to project power globally and hold hostile actors accountable for threatening international stability and supporting terrorism. This decisive action protects American interests and allies while exposing the vulnerabilities of nations that challenge our military capabilities. The operation underscores the importance of maintaining the world’s most advanced submarine fleet as a cornerstone of national defense and deterrence strategy.
Sources:
US submarine strike sinks Iranian warship for first time since WWII
U.S. Submarine Sinks Iranian Warship In The Indian Ocean
