Nineteen sailors have been killed and another 15 injured after an Iranian warship accidentally struck another with a missile during an exercise in the Gulf of Oman.

According to state media, the frigate Jamaran fired at a training target released by a support ship, the Konarak, which failed to leave area in time and was hit.

Iranian media rarely report on mishaps during its exercises, signalling the severity of the incident, which happened on Sunday.

The friendly fire incident happened near the port of Jask, some 790 miles south-east of Tehran, in the Gulf of Oman, a sensitive waterway that connects to the Strait of Hormuz through which about a fifth of the world’s oil passes.

A local hospital admitted 12 sailors and treated another three with slight wounds, the state-run IRNA news agency reported.

Iranian media said the Konarak had been overhauled in 2018 and was able to launch sea and anti-ship missiles.

The Dutch-made vessel was in service since 1988 and had capacity of 40 tonnes. It usually carries a crew of 20 sailors, Reuters reports. 

The incident also comes amid months of heightened tensions between Iran and the US since President Donald Trump unilaterally withdrew from Tehran’s nuclear deal with world powers in 2018 and imposed crushing sanctions on the country.

Animosity deepened in early January when a US drone strike in Baghdad killed top Iranian military commander Qassem Soleimani. 

Iran retaliated on January 9 by firing missiles at US military bases in Iraq.

Later that day, Iran’s armed forces shot down a Ukrainian airliner, killing all 176 people aboard, in what the military later acknowledged was a mistake.