Sinking of IRIS Dena

4 min read Original article ↗

From Wikipedia, the free encyclopedia

Sinking of Iranian ship during 2026 Iran war

The Iranian frigate IRIS Dena was torpedoed and sunk by an American submarine in the Indian Ocean on 4 March 2026, approximately 40 nautical miles (74 km; 46 mi) south of Galle, Sri Lanka. The United States Department of Defense later confirmed that the attack was carried out using a Mark 48 torpedo.[1] It was the first acknowledged instance of a submarine sinking an enemy surface vessel since the sinking of ARA General Belgrano during the Falklands War,[a] and the first torpedoing of a ship by an American submarine since World War II.[2]

IRIS Dena was a Moudge-class frigate commissioned in 2021. In February 2026, the vessel had been participating in the multinational naval exercise MILAN 2026 and the International Fleet Review at Visakhapatnam, India.[3]

The incident took place amid a significant escalation in the 2026 conflict between Iran, Israel, and the United States, which included U.S.–Israeli airstrikes on targets within Iran earlier that week.

IRIS Dena in 2021

  • The ship being struck

    The ship being struck

  • The ship sinking

IRIS Dena was sunk in the early morning hours of 4 March 2026, after being torpedoed by a United States Navy submarine. The vessel was positioned approximately 40 nautical miles (74 km; 46 mi) off the coast of Galle, Sri Lanka, within the country's exclusive economic zone, when the strike occurred. According to the Sri Lankan Ministry of Foreign Affairs, Dena issued a distress call at 5:08 a.m. local time reporting an explosion, but the ship sank shortly thereafter before rescue forces could reach the location.

The fleet was reportedly returning from the International Fleet Review 2026 and the joint exercise MILAN held at Visakhapatnam, India. At the time of the incident, there were approximately 180 people on board the frigate. Reports indicate that at least 87 individuals were killed in the attack. Thirty-two survivors were successfully rescued and transported to the Karapitiya Teaching Hospital in Galle, where they received medical treatment for exhaustion and injuries related to the blast. Sixty-one others remained missing.[4]

During a briefing at The Pentagon, U.S. Secretary of War Pete Hegseth confirmed that an American submarine had intercepted and fired upon the Iranian frigate. Hegseth described the engagement as a "quiet death." Following the strike, the Sri Lankan Ministry of Defence confirmed that the vessel had submerged in international waters prior to the arrival of emergency teams.[5]

  1. ^ IRIS Dena was also preceded by the 2010 sinking of South Korean corvette Cheonan, presumed to have been torpedoed by a North Korean midget submarine; however, no party officially claimed responsibility.
  1. ^ Simkins, J. D.; Ceder, Riley (4 March 2026). "US submarine sinks Iranian ship in first torpedo kill since WWII, Pentagon confirms". Military Times. Archived from the original on 4 March 2026. Retrieved 4 March 2026.
  2. ^ "US sub sinks Iranian warship in Indian Ocean, Hegseth says". www.bbc.com. 4 March 2026. Retrieved 5 March 2026.
  3. ^ "Sri Lanka rescues 32 sailors from sunk Iranian warship, recovers 'few bodies'". The Hindu. 4 March 2026. Retrieved 4 March 2026.
  4. ^ "Iris Dena news Live Updates: US says Iran's warship Iris Dena sunk in torpedo attack near Sri Lanka, at least 87 dead". Hindustan Times. 4 March 2026. Retrieved 4 March 2026.
  5. ^ "Iran latest: Around 140 people missing after Iranian navy ship sinks near Sri Lanka". BBC News. 4 March 2026. Archived from the original on 4 March 2026. Retrieved 4 March 2026.
  6. ^ Edgington, Tom (4 March 2026). "Hegseth wrong to say 'first torpedo sinking since WW2'". BBC News. Retrieved 4 March 2026.