State media initially reported that at least one person was killed in the accident.

"The incident took place in the area near the southern Iranian port city of Jask in the Gulf of Oman during an Iranian naval exercise," a newsreader said during a broadcast on state television earlier.

Regular exercises

The semi-state news agency Fars reports that the robot hit the ship Konarak. The robot was fired from the vessel Jamaran, according to Tasnim, another semi-state news agency.

The Gulf of Oman is a sensitive area as it connects to the strategically important Strait of Hormuz where one fifth of the world's oil is transported.

As a result, Iran's navy and army regularly conduct exercises in the Gulf of Oman.