Several people have been injured after an Iranian naval frigate capsized and sunk while repairs were being carried out on it at a port, state media has said.

Pictures on social media showed the Sahand destroyer rolled over on its side.

The incident happened in the southern port of Bandar Abbas, near the Strait of Hormuz, after water got into the ship's tanks, said the IRNA news agency.

It said it was possible to rebalance the frigate as the incident happened at a low depth in the water.

State media also said several people were taken to hospital with minor injuries.

"As Sahand was being repaired at the wharf, it lost its balance due to water ingress. Fortunately... the vessel is being returned to balance quickly," IRNA reported, citing a navy statement.

Sahand, which was named after a mountain in northern Iran, took six years to build and was launched into the Persian Gulf in December 2018.

The 1,300-tonne vessel had surface-to-surface missiles and surface-to-air missiles, as well as anti-aircraft batteries and sophisticated radar and radar-evading capabilities.

There have been reports that since it was built, the ship had been upgraded to include a new radar, four to eight medium-range air-defence missiles and double the number of anti-ship missiles.

This may have raised her centre of gravity, it has been reported by navalnews.com.

It is not the first time an Iranian warship has sunk.

The same thing happened to Damavand in the Caspian Sea in January 2018 after it crashed into a breakwater - a permanent structure built to protect against tides, currents, waves, and storm surges.

In June 2021, another warship, the Kharg, sank after catching fire in the Gulf of Oman, Iranian media reported.