Armed or Unarmed? U.S. and Iran Clash Over Sunk Iranian Warship

U.S. and Iran Dispute Details of Iranian Warship Sinking

The United States and Iran have provided conflicting accounts regarding the sinking of an Iranian warship in the Indian Ocean last week. Washington has denied Tehran’s claim that the vessel was unarmed, while Iranian officials maintain that the ship was engaged in a noncombat role.

The United States Indo-Pacific Command (INDOPACOM) rejected Iran’s assertion that the warship IRIS Dena was unarmed when it was sunk in a submarine attack in international waters off Sri Lanka on March 4. In a statement on X, INDOPACOM labeled Iran’s claim as “false.”

This response came after strong objections from Tehran, which has repeatedly described the warship as defenseless, stating it was returning home after participating in a naval exercise. An Indian navy official, who spoke on condition of anonymity, mentioned that the Iranian vessel was not “entirely unarmed” and had participated in drills alongside other countries’ warships.

Some experts suggest that visiting ships at such events typically do not carry a full combat load of live munitions unless scheduled for live-fire drills. They add that even during the sea phase of exercises, ships usually carry only tightly-controlled ammunition limited to specific drills.

Rahul Bedi, an independent defense analyst based in India, noted that the vessel may have used some limited non-offensive ammunition during the naval exercises, but protocol requires “the participating platforms to be unarmed.” He explained, “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.”

Iran’s Deputy Foreign Minister Saeed Khatibzadeh claimed that the warship, sunk by a U.S. torpedo, had not been carrying weapons and accused Washington of targeting 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 stated to reporters in New Delhi.

The IRIS Dena was sunk on March 4 in the Indian Ocean near Sri Lanka after being struck by a torpedo fired from a U.S. submarine, according to American and Iranian officials. The Sri Lankan navy rescued 32 sailors and recovered 87 bodies.

U.S. Defense Secretary Pete Hegseth referred to the IRIS Dena as a “prize ship” and said it “died a quiet death.” Iran’s Foreign Minister Abbas Araghchi called the attack “an atrocity at sea” and emphasized that it had been “a guest of India’s Navy.”

Disputes over whether the vessel was armed have heightened tensions surrounding the incident, which occurred as it was returning from multinational naval exercises in India. This has raised questions about whether it was operating in a noncombat role when it was attacked.

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

The warship’s sinking underscores how the U.S.-Israeli conflict with Iran is extending beyond the Middle East. Two other Iranian vessels—the IRIS Bushehr and IRIS Lavan—are currently docked in Sri Lanka and India after seeking assistance from the two countries.