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The Iranian military on Tuesday seized a Western cargo ship in the Persian Gulf, the Pentagon said, briefly roiling markets. (Tweet This) Warning shots were fired but no injuries were reported, a shipping agency said. Thirty-four crew members were reported aboard.
The Iranian navy seized the ship at the request of the Iran Ports Authority under a court order, according to the English service of Iran's Fars News Agency.
The seizure happened with tensions high in the region. Saudi Arabia recently engaged in a bombing campaign in strife-torn Yemen against Iranian-backed Houthi rebels.
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U.S. defense officials said the ship was seized in the Strait of Hormuz and was under control of the Iranian Revolutionary Guard. They said that while the USS Farragut was headed toward the area, the U.S. destroyer has no authority to enter the territorial waters for any other purpose than "innocent passage" through the strait.
The Pentagon said the Marshall Islands-flagged Maersk Tigris did not have any U.S. citizens aboard.
Al Arabiya, the Saudi news network, initially reported that a U.S. vessel has been fired on and steered to the Bandar Abbas port by Iran.
The Fars News Agency reported that an "American trade vessel" had been confiscated.
The Pentagon called the Iranian firing of warning shots at the ship "inappropriate"and said it was reviewing U.S. defense obligations to the Marshall Islands in light of the seizure. The U.S. historically contributes to the defense of the Marshall Islands but defense officials could not say whether the American military was obligated to intervene.
Fars reported that "the vessel had been seized for trespassing on Iran's territorial waters in the Persian Gulf." Another Iranian news agency, Tasnim, reported that the confrontation did not have a "military or political dimension and is a civil matter."
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Cor Radings, a spokesman for Rickmers Ship Management, which manages the Maersk Tigris, told NBC that "the ship is at least partially, possibly 100 percent, owned by American investors."
"Since then we have lost contact with the ship but are monitoring its movements. Obviously the safety of the crew is our main priority at this time. They were only warning shots, they did not hit the ship, there was no damage nor any injuries," said Radings.
Oil futures surged on the news but later settled. U.S. stocks were higher in early afternoon trading.
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According to information on the ship tracking website Marine Traffic, the vessel was destined for the United Arab Emirates. The ship is 255 meters (836 feet) in length and was built in 2014, according to the website.
A senior U.S. administration official said the ship issued distress calls after the Iranians fired warning shots, and the calls were received by U.S. forces operating in the region.
Senior U.S. Navy officials told NBC News there had not been any confrontation between Iran's Revolutionary Guard and any Navy ships.
The cargo ship is reported to have 34 crew members aboard and was steered to the port on the southern coast of Iran, according to Al Arabiya.
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It is not clear yet what type of cargo the ship was carrying.
A spokesperson from Maersk told NBC News that the Maersk Tigris was being run on a "time charter" by Rickmers Ship Management, which lists its head offices as Hamburg and Singapore. The tracking website Marine Traffic lists the former name of the Maersk Tigris as "Wide Golf."
—Reuters and NBC contributed to this report.