Nigeria, March 5 -- The US announced on Wednesday that it sank an Iranian warship returning from a naval exercise organised by India in the Bay of Bengal, in the north of the Indian Ocean.

The warship was sunk by a torpedo fired by a US submarine off the south coast of Sri Lanka, leaving 87 Iranian sailors dead and about 100 others missing, according to Sri Lanka's Foreign Ministry. The US made no effort to rescue the survivors.

Sri Lanka also disclosed that, based on the ship's documentation, around 180 people were believed to have been aboard the Iris Dena.

The US attack on the warship, which was not taking part in the hostilities, expands the war beyond the Gulf countries to the Indian Ocean and to India's backyard.

Reuters reports...