Iranian media reports that the country's largest naval vessel, the replenishment tanker Kharg, sank in the Gulf of Oman on Wednesday, June 2.
The Islamic Republic of Iran Navy (IRIN) said the 207-metre vessel was participating in a training exercise in international waters off the port of Jask when a fire broke out on board on Tuesday, June 1.
An IRIN spokesperson said the subsequent firefighting effort on Kharg lasted 20 hours but was ultimately unsuccessful, and the crippled ship slipped beneath the waves at 08:30 local time on Wednesday.
All 400 of the ship's crew were rescued. No casualties have been reported, though 33 individuals have suffered non-life-threatening injuries.
Local authorities have not yet issued an official statement on the cause of the fire.
Kharg was originally built in the UK in 1977 and has been on active duty with the IRIN since its acquisition in 1984.