US military 'monitoring' Iran ship seizure

Pentagon officials say the US is monitoring the seizure by Iran of a Marshall Islands-flagged cargo ship.

The MV Maersk Tigris was moving through Iranian waters in the Straits of Hormuz on Tuesday when Iranian patrol vessels fired warning shots, according to the Pentagon.

The ship was then ordered deeper into Iranian waters, the Pentagon said.

A US naval destroyer has been ordered to the region to "monitor" the situation.

An initial report by the Saudi-owned Al-Arabiya TV network suggested that the vessel was a US cargo ship with 32 Americans on board.

But a Pentagon spokesman told ABC news that a ship bearing the flag of the Marshall Islands - an island country in the Pacific Ocean roughly halfway between the US and Iran - had been boarded by the Iranian navy.

The cargo ship could be seen on maritime tracking website a few miles from Bandar Abbas, a port city on the southern coast of Iran that occupies a strategic position on the narrow Strait of Hormuz in the Persian Gulf and houses one of the Iranian Navy's main bases. 

The Marshall Islands is a presidential republic in free association with the US which provides the islands with subsidies and access to social services.

With few natural resources, the islands' wealth is based on a service economy as well as some fishing and agriculture; aid from the US represents a large percentage of the islands' gross domestic product. The country uses the US dollar as its currency.