New Delhi, March 5 -- At least 87 people have been confirmed dead, while many more are unaccounted for after a US submarine struck IRIS Dena, an Iranian frigate off the coast of Sri Lanka on Wednesday. While the Sri Lankan Navy rescued 32 Iranian sailors, an estimated 60 people on board remain unaccounted for.

The sinking of IRIS Dena was the first time since World War II that a US submarine had sunk another vessel using a torpedo.

IRIS Dena, a 1,500-ton Moudge-class frigate, was on its way to Iran after taking part in a multilateral maritime exercise in the Bay of Bengal.

IRIS Dena, which was launched in 2015 and commissioned into the Iranian Navy in 2021, was a destroyer equipped with four Iran-made engines "Bonyan 4" and a vertical ...