A U.S. submarine torpedoes and sinks a warship off the southern coast of Sri Lanka, dramatically expanding the scope of the U.S. government’s pursuit of Iran’s navy.

Sri Lankan Foreign Minister Arun Hemachandra identified the warship as the frigate Iris Dena, which was returning to Iran from a port in eastern India.

The attack occurred hundreds of kilometers across the Indian Ocean from the Persian Gulf, where U.S. and Israeli forces have attacked Iran and Tehran has retaliated with missile and drone strikes.

“A U.S. submarine sank an Iranian warship that we thought was safe on the high seas,” U.S. Army Secretary Pete Hegseth said Wednesday at the Pentagon in Arlington, Virginia. “Instead, it was torpedoed and sunk. It was a quiet death.”

Hospital authorities in the Sri Lankan port city of Galle said 87 bodies had been brought in by military rescue workers who responded to an early morning distress call. Sri Lankan authorities said 32 more people were rescued and were being treated in hospitals, and about 60 of the estimated 180 people on board were likely missing.

A Pentagon video shared on social media purporting to capture the attack showed the warship hit by a huge explosion, the back of the ship blown off, the ship rising out of the water and beginning to sink stern-first.

The exact date the video was taken and the type of warship could not be confirmed. However, the deck shape and mast of the ship in the video matched file images of a warship of the same type as IRIS Dena.

A ship named IRINS Dena was listed to participate in the naval exercise held in the Bay of Bengal from February 18 to February 25, according to the exercise’s website. IRIS (Islamic Republic of Iran Ships) is the more commonly used prefix for Iranian naval vessels, although ⁠IRINS, for Islamic Republic of Iran Naval Ships, is also used.

“Let me remind everyone that this is an incredible demonstration of America’s global influence in tracking, locating, and killing out-of-range destroyers.” [and] “This is something only the United States can do on this kind of scale,” said Gen. Dan Cain. Chairman of the United States Joint Chiefs of Staff.

Kane said the torpedo sent the ship to the “bottom of the ocean.” Central Command said Wednesday that American forces have attacked or sunk more than 20 Iranian ships since the conflict with Tehran began last week.

Just outside Sri Lankan waters

Sri Lanka announced that it had begun a search and rescue operation to find survivors after receiving a distress call.

Sri Lanka Navy Spokesperson Commander. Bodhika Sampath said that the boats that arrived at the scene could only see an oil slick, adding that although the incident occurred outside Sri Lankan territorial waters, Colombo remains committed to providing assistance.

“We found people floating in the water and rescued them,” Sampath told reporters. “Later, we found out that they belonged to an Iranian ship.”

Rescuers transported the bodies covered in white sheets in several trucks by truck to Karapitiya Hospital in Galle, where they were transferred to a mortuary.

Survivors included the warship’s commander and several senior officers, who told the Sri Lankan navy that it had been attacked by a submarine, two Sri Lankan sources told Reuters.

The website for Milan, a biennial multilateral naval exercise hosted by India, states that IRINS Dena participated in the exercise, which was held in the Bay of Bengal off India’s east coast.

The Indian Navy welcomed the arrival of the “Iranian Navy’s” Iris Dena in a Feb. 17 post on social media platform X.

An Indian Navy spokesperson did not respond to a Reuters request for comment after the Dena sank.