TEHRAN, Iran (AP) — The largest ship in the Iranian navy caught fire early Wednesday in the Gulf of Oman under unclear circumstances, forcing sailors to evacuate the vessel, state media reported.

A state television report identified the vessel as the support ship Kharg, named after the island that serves as the main oil terminal for Iran.

The blaze began around 2:25 a.m. and firefighters were still trying to contain it, state TV said. The vessel is near the Iranian port of Jask, some 1,270 kilometers (790 miles) southeast of Tehran on the Gulf of Oman near the Strait of Hormuz — the narrow mouth of the Persian Gulf.

The state-run IRNA news agency later said the “rescue operation for the Kharg failed," without elaborating on what that meant.

Photos circulated on Iranian social media of sailors wearing life jackets evacuating the vessel as a fire burned behind them. State TV and semiofficial news agencies referred to the Kharg as a “training ship.”

The Kharg serves as one of a few vessels in the Iranian navy capable of providing replenishment at sea for its other ships. It also can lift heavy cargo and serve as a launch point for helicopters. The ship, built in Britain and launched in 1977, entered the Iranian navy in 1984 after lengthy negotiations that followed Iran's 1979 Islamic Revolution.

The incident marks the latest naval setback for Iran. In 2020 during an Iranian military training exercise, a missile mistakenly struck a naval vessel near the port of Jask, killing19 sailors and wounding 15. Also in 2018, an Iranian navy destroyer sank in the Caspian Sea.