US, Iran Clash Over Whether Sunken Warship Was Armed During Attack

The United States and Iran are disputing whether an Iranian warship was carrying weapons when it was torpedoed by a U.S. submarine in the Indian Ocean on March 4. Iran claims the vessel was unarmed and returning from ceremonial naval exercises, while the U.S. military rejects that characterization.

NEW DELHI (AP) — A diplomatic dispute has erupted between Washington and Tehran following the submarine attack that destroyed an Iranian naval vessel in the Indian Ocean, with both nations presenting conflicting narratives about whether the ship carried weapons.

U.S. Indo-Pacific Command dismissed Iranian assertions on Sunday that the warship IRIS Dena lacked armaments when it was torpedoed in international waters near Sri Lanka on March 4. Military officials used social media platform X to label Iran’s claims as “false.”

Tehran has consistently maintained that the destroyed vessel posed no threat, describing it as defenseless while returning from participation in multinational naval drills.

An unnamed Indian naval official, who spoke without authorization to discuss the matter publicly, indicated the Iranian ship wasn’t “entirely unarmed” and had participated in exercises with vessels from multiple nations.

Defense experts note that ships attending such international events typically don’t carry full ammunition loads unless live-fire training is planned. During maritime exercises, vessels usually transport only restricted munitions designated for specific training purposes.

Independent defense analyst Rahul Bedi, based in India, explained that while the ship might have carried limited non-combat ammunition during the naval exercises, standard procedures demand “the participating platforms to be unarmed.”

“The precondition of participating in such a parade, or such a ceremony, is that it (the vessel) comes unarmed. That is the precondition of the Indian Navy and it’s a precondition of most navies when they hold such similar sort of fleet reviews,” Bedi said.

Iranian Deputy Foreign Minister Saeed Khatibzadeh declared Friday that the warship, destroyed by an American torpedo, carried no weapons and criticized Washington for attacking a ceremonial vessel.

“That vessel was by invitation of our Indian friends, attending an international exercise. It was ceremonial. It was unloaded. It was unarmed,” he told reporters in New Delhi.

The IRIS Dena went down March 4 in Indian Ocean waters near Sri Lanka after a torpedo strike from an American submarine, according to officials from both countries. Sri Lankan naval forces saved 32 crew members and retrieved 87 bodies from the water.

Defense Secretary Pete Hegseth called the IRIS Dena a “prize ship” and remarked it “died a quiet death.” Iranian Foreign Minister Abbas Araghchi condemned the attack as “an atrocity at sea” and emphasized the vessel had been “a guest of India’s Navy.”

Arguments over the ship’s armament status have escalated tensions surrounding the incident, which happened as the vessel traveled home from India’s multinational naval exercises, sparking debate about whether it operated in a non-combat capacity during the attack.

India’s defense ministry noted in post-exercise statements that “live firings as part of surface gun shoots, as well as anti-air firings, were also undertaken” by participating vessels.

The warship’s destruction demonstrates how the U.S.-Israeli conflict with Iran is expanding beyond Middle Eastern boundaries.

Two additional Iranian ships — the IRIS Bushehr and IRIS Lavan — remain docked at ports in Sri Lanka and India after requesting aid from both nations.