Iran forces Marshall Islands-flagged cargo ship to Iranian port

Iranian military ships fired across the bow of a Marshall Islands-flagged cargo vessel in the strategic Strait of Hormuz on Tuesday and forced it to head to Iranian territory, US officials said.

The cargo ship had last made a stop at the Red Sea port of Jeddah, on the Saudi Arabian coast, according to the website maritimetraffic.com, and was sailing through the strait into Gulf waters.

It was unclear if the last port of call was related to the Iranian decision to take control of the container ship. Iran and Saudi Arabia are waging a proxy war in Yemen, where Saudi-led aircraft are bombing Shiite Huthi rebels backed by Tehran.

At about 0900 GMT, at least five ships from Tehran's elite Revolutionary Guards demanded that the Maersk Tigris, which had no Americans on board, head toward Iran's Larak Island, the Pentagon said.

The cargo ship's captain "declined" the demand and one of the Iranian vessels fired shots across its bow, Pentagon spokesman Colonel Steven Warren said.

The cargo ship, Warren said, then "complied with the Iranian demand and proceeded into Iranian waters in the vicinity of Larak Island."

Members of the Revolutionary Guards boarded the cargo ship, which issued a distress call over an open radio channel.

The US military's Central Command heard the distress call and ordered a naval destroyer, the USS Farragut, to the area.

US naval aircraft are monitoring the situation, Warren said.

The destroyer was directed "to proceed at best speed to the nearest location of the Maersk Tigris," he said.

But it was "unlikely" that the US destroyer would enter Iran's territorial waters.

Asked about Iran's actions, Warren said "it seems to be provocative behavior but we don't have all the facts yet."

It was "too early" to say whether the incident represented an attempt by Tehran to disrupt commercial shipping in the waterway, Warren added.

- 'Innocent passage' -

 The cargo ship was approached by the Iranians along a standard shipping lane used by commercial vessels, which lies in Iran's territorial waters, officials said.

Under maritime law governing the narrow Strait of Hormuz, commercial ships have the right of to move through Iran's territorial waters, under the principle known as "innocent passage," officials said.

The US government provides defense and subsidies for the Marshall Islands and officials could not say if Washington was required to take action under its ties with the Pacific nation.

"We do have certain obligations and we're working through that," Warren said.  

The cargo ship had a crew of more than 30 people and was believed to be leased by A.P. Moeller-Maersk, a Danish shipping and oil conglomerate. The group includes a US-based subsidiary that does contract work for the US military.

The confrontation came amid heightened sectarian tensions in the region as Saudi Arabia and its Gulf allies carry out air strikes in Yemen against Iranian-backed Huthi rebels.

The United States is providing intelligence and aerial refueling for the Saudi-led coalition.

Nine US warships, including an aircraft carrier and destroyers, recently deployed to the waters off Yemen for a potential showdown with an Iranian convoy of cargo ships that American officials suspected was carrying arms destined for Huthi forces in Yemen.

But the convoy last week turned back and headed north towards Iran.