US sub sinks Iranian warship off Sri Lanka, killing 87 and expanding war zone

A U.S. Navy submarine sank an Iranian warship off the southern coast of Sri Lanka on Wednesday, killing at least 87 sailors, according to U.S. and Sri Lankan officials.

U.S. Defense Secretary Pete Hegseth said the submarine fired a torpedo at the Iranian frigate IRIS Dena while it was transiting international waters in the Indian Ocean, describing the strike as a “quiet death.”

Hospital authorities in the Sri Lankan port city of Galle said 87 bodies were brought in by military rescuers responding to an early morning distress call, and another 32 sailors were rescued and were being treated at a local hospital.

About 60 people were still unaccounted for from an estimated 180 aboard the vessel, Sri Lankan officials said.

A Pentagon video purporting to show the attack depicted a huge explosion that blew apart the rear of the warship, lifting it from the water before it began sinking by the stern. The date and exact location of the footage could not be independently verified, but the imagery matched the Dena’s profile.

Sri Lanka’s navy said its boats that reached the reported site observed only an oil slick, indicating the ship had quickly sunk. Commander Buddhika Sampath, a navy spokesman, said rescuers found people floating in the water and later confirmed they belonged to the Iranian vessel.

Rescuers brought bodies, covered in white sheets, to Karapitiya Hospital in Galle, where they were moved to the morgue, and survivors were treated for injuries from the blast and exposure.

The Dena had taken part in the biennial multinational naval exercise “Milan,” organised by India in the Bay of Bengal from Feb. 18 to 25, according to the exercise’s organisers. Images shared by India’s Eastern Naval Command on social media showed the Dena and its officers at the event earlier this month.

An Indian Navy spokesperson did not immediately respond to a request for comment after the attack was reported.

The sinking marks a sharp escalation of hostilities in the broader conflict between the U.S., its partners, and Iran. U.S. forces have recently intensified operations against Iranian naval assets and other military targets, officials said.

Sri Lankan authorities, although not a party to the conflict, launched a search-and-rescue operation after receiving the distress call and stressed their commitment to helping survivors despite the incident occurring outside Sri Lankan territorial waters.