Explosions were heard near the Strait of Hormuz and Bandar Abbas, Iran's semi-official Tasnim news reported on Thursday night.
Tasnim later reported that the sounds came from exchanged fire made in warning to ships in the Strait of Hormuz.
Semi-official Fars news agency said early on Thursday that Iran's armed forces carried out a missile launch operation from the southern region of the country toward specified targets, and that the destination of the missiles was not yet clear.
This is a developing story.