The Pentagon has said an Iranian patrol boat has fired shots at a Marshall Islands flagged cargo ship and ordered it to sail deeper into Iranian waters.

US aircraft and the missile destroyer ship the USS Farragut have responded to a distress call from the MV Maersk Tigris, which was travelling through the Strait of Hormuz when it came under fire.

Iranian forces are also thought to have boarded the Maersk Tigris, which is flagged to the Marshall Islands.

At least five Iranian ships are reported to have intercepted the vessel, which has no US citizens on board. It is thought to be heading towards Larak Island.

US Army Colonel Steve Warren said the cargo ship initially ignored the patrol boats, but complied after the vessels fired several warning shots.