According to semi-official news outlets, Iran's largest warship caught fire and drowned in the Gulf of Oman under mysterious circumstances.

According to the Fars and Tasnim news agencies, efforts to salvage the support warship Kharg, which is named after the island that serves as Iran's primary oil terminal, were unsuccessful.

According to Fars, the fire started about 2.25 a.m. and firefighters attempted to put it out.

The ship sank at the Iranian town of Jask, some 790 miles southeast of Tehran, in the Gulf of Oman, near the narrow opening of the Persian Gulf known as the Strait of Hormuz.

Sailors wearing life jackets departing the vessel as a fire flared behind them were photographed and posted on Iranian social media.

The Kharg was referred to as a "training ship" by state television and semiofficial news sources.

Early Wednesday morning, Fars tweeted a video of heavy, black smoke coming from the ship.

The Associated Press analyzed satellite photographs from Planet Labs Inc on Tuesday, which showed the Kharg off to the west of Jask.

Satellites from the US National Oceanic and Atmospheric Administration, which follow fires from space, identified a wildfire at the Jask facility that began just before the fire reported by Fars.

The Kharg is one of the few ships in the Iranian navy capable of replenishing its sister ships while at sea.

It can also carry big loads and function as a helicopter launch pad.

After prolonged discussions following Iran's 1979 Islamic Revolution, the battleship, built in Britain and launched in 1977, was accepted into the Iranian navy in 1984.

The Iranian navy patrols the Gulf of Oman and the surrounding seas, while the Revolutionary Guard operates in the shallower waters of the Persian Gulf and the Strait of Hormuz.

However, the navy just launched the Makran, a slightly larger commercial tanker that was adapted to serve a similar duty as the Kharg.

The cause of the fire aboard the Kharg was not given by Iranian officials.

However, it comes after a series of mysterious explosions in the Gulf of Oman that began in 2019.

The US Navy later accused Iran of using limpet mines, timed explosives normally placed to a vessel's hull by divers.

Despite US Navy videotape showing members of Iran's Revolutionary Guard removing one unexploded limpet mine from a vessel, Iran denied targeting the vessels.

The occurrences occurred amid rising tensions between the United States and Iran following President Donald Trump's unilateral withdrawal from the international nuclear deal with Iran.

The sinking of the Kharg is Iran's most recent naval disaster.

A missile accidentally struck a navy vessel at the port of Jask in 2020 during an Iranian military training exercise, killing 19 sailors and injuring 15.

A warship of the Iranian navy lost in the Caspian Sea in 2018.