An Iranian naval warship was sunk by a United States submarine in the Indian Ocean near Sri Lanka’s southern coast, killing dozens of sailors and significantly expanding Washington’s military campaign against Iran’s naval forces, according to Reuters.

Sri Lanka’s deputy foreign minister said the vessel was the Iranian frigate IRIS Dena, which was returning to Iran after visiting an eastern Indian port. The incident occurred hundreds of miles from the Persian Gulf, where US and Israeli forces have been conducting strikes against Iran amid escalating hostilities between Tehran and its adversaries.

US Defense Secretary Pete Hegseth confirmed the attack at the Pentagon, saying an American submarine had torpedoed the Iranian ship in international waters.

“An American submarine sank an Iranian warship that believed it was safe in international waters,” Hegseth said. “Instead, it was struck by a torpedo. Quiet death.”

Sri Lankan authorities said rescue teams responding to an early morning distress call recovered dozens of casualties from the sea. Hospital officials in the southern port city of Galle reported that 87 bodies had been brought to the Karapitiya Hospital morgue.

Another 32 sailors were rescued and are receiving medical treatment, while about 60 crew members remain missing from an estimated 180 personnel believed to have been aboard the vessel.

Sri Lanka’s navy said the incident took place outside its territorial waters but that Colombo launched a search-and-rescue operation after receiving the distress signal.

Navy spokesman Commander Buddhika Sampath said rescue boats arriving at the scene initially found only an oil slick before spotting survivors in the water.

“We found people floating in the water and rescued them,” Sampath told reporters. “Later we learned they were from the Iranian ship.”

Survivors, including the ship’s commander and several senior officers, told Sri Lankan naval authorities that the vessel had been struck by a submarine-launched torpedo, two Sri Lankan sources told Reuters.

The Pentagon also released video footage it said showed the moment of the attack. The video appears to capture a large explosion tearing through the rear section of a warship, lifting part of the vessel out of the water before it begins sinking stern-first. Reuters said it could not independently verify when the footage was recorded, but the ship’s structure appeared consistent with images of the IRIS Dena.

According to the website of the MILAN naval exercise, a biennial multinational drill organized by the Indian Navy, the IRIS Dena had recently participated in the exercise held in the Bay of Bengal from February 18 to 25.

Images posted earlier by India’s Eastern Naval Command showed the Iranian frigate arriving in Visakhapatnam for the exercise, highlighting naval cooperation among participating countries. An Indian Navy spokesperson did not immediately respond to requests for comment following the sinking.

The strike marks one of the most distant confrontations in the rapidly widening conflict involving Iran and the United States, underscoring how the war is spreading beyond the Middle East into the broader Indian Ocean region.

BOB Post