Sri Lanka said it was trying to "safeguard lives" on a second Iranian ship off its coast on Thursday, a day after 87 people were killed in a US submarine strike on an Iranian warship in the same region, an attack that Iran said the US would "bitterly regret".
Sri Lanka's cabinet spokesman told parliament that Colombo was aware that there was another Iranian ship in Sri Lanka's exclusive economic zone outside its maritime boundary and it was, "addressing the situation".
The cabinet spokesman was responding to questions from an opposition leader on whether the government was aware that another Iranian ship was near the port of Colombo. "The President, defence officials, and all other relevant officials are aware and we are addressing the situation," spokesman Nalinda Jayatissa said.
"We are doing our utmost to safeguard lives." He did not say on whether the ship was a military vessel or not.
Jayatissa said that the IRIS Dena was sunk 19 nautical miles (35.2 kilometres) off Sri Lanka's southern port city of Galle and that two freezers had been dispatched from Colombo to store the 87 bodies recovered from the sea on Wednesday.
Iranian Foreign Minister Abbas Araqchi said the warship was struck in international waters without warning thousands of miles from the Gulf, where US and Israeli forces are striking Iran and Tehran is retaliating with missile and drone attacks.
"The US will bitterly regret the precedent it has set," Araqchi said in a post on social media, adding that the warship was a guest of India's navy and was carrying almost 130 sailors.
Sri Lankan military rescuers responded to an early-morning distress call from the IRIS Dena on Wednesday and found 32 survivors. Search and rescue operations for an estimated 10 people who remain unaccounted for would continue on Thursday, authorities said.
The 32 rescued sailors were being treated for minor injuries and could be released from hospital on Thursday, they said. Two policemen guarded the entrance to ward number 58 of the hospital as nurses milled about and doctors conducted morning rounds.
The attack dramatically widens the scope of the war. "An American submarine sank an Iranian warship that thought it was safe in international waters," US Defence Secretary Pete Hegseth said at the Pentagon. "Instead, it was sunk by a torpedo. Quiet death."
A Pentagon video purporting to have captured the attack showed the warship being hit by a huge explosion, which blew apart the rear of the vessel, lifting it from the water, and causing it to begin sinking from the stern.
IRIS Dena had taken part in a naval exercise organised by India in the Bay of Bengal from February 18 to 25 and was on its way back, according to the drill's website and Sri Lankan officials. An Indian Navy spokesperson did not respond to a request for comment after the Dena was sunk.
The Sri Lankan Government remains in close contact with international maritime agencies to monitor the movement of any further vessels in the exclusive economic zone. Defence officials confirmed that patrol boats have been stationed to maintain security in the southern waters following the incident.
Regional tensions have escalated following the sinking of the IRIS Dena, with several neighbouring countries expressing concern over the safety of commercial shipping lanes in the Indian Ocean. Maritime security experts suggest that the incident could lead to increased patrols by international naval forces in the area.
Local authorities in Galle have coordinated with the Iranian embassy to manage the repatriation of the recovered bodies. The process is expected to begin once formal identification has been completed by medical staff at the hospital.
(Reporting by Uditha Jayasinghe in Galle and Jana Choukeir and Elwely Elwelly in Dubai; Writing by Shilpa Jamkhandikar and YP Rajesh; Editing by Saad Sayeed and Philippa Fletcher)