Iran’s Islamic Revolutionary Guard Corps has seized a tanker in the Gulf of Oman, it was reported on Thursday.
The Advantage Sweet oil tanker, flagged under the Marshall Islands, sent a distress call and the US Fifth Naval Fleet is monitoring the situation, naval command said in a statement.
The 270-metre vessel was en route to Houston, Texas, when it was intercepted, tracking website MarineTraffic reported. It left Mina Saud Port on the south coast of Kuwait on Tuesday.
The ship is owned by Advantage Tankers LLC.
The IRGC’s actions are “contrary to international law and disruptive to regional security and stability”, US Naval Command added, calling on Iran to “immediately release” the vessel.
“Iran’s continued harassment of vessels and interference with navigational rights in regional waters are a threat to maritime security and the global economy,” Washington said.
Iran's army said in a statement to the Tasnim News Agency that a ship had been seized after two people were missing and others injured in an "accident between an unknown ship and an Iranian vessel".
It said the unknown ship, which had a Marshall Islands flag, had "acted against the international regulations to help the vessel and the injured".
US Central Command chief Gen Michael Kurilla called the seizure "another in a continuing series of violations by Iran of the international rules-based order".
"This kind of harassing activity is commensurate with an established pattern of Iranian behaviour that places the security and the stability of the Middle East at risk," Gen Kurilla added.
It comes only a week after the US sailed its first drone boat through the strategic Strait of Hormuz, often the site of tensions between Washington and Tehran.
The Fifth Fleet launched a special drone task force last year, aiming to have about 100 unmanned drones, sailing and submersible, operating in the region alongside America’s allies.
Iran briefly seized several of the US drones being tested in the region in late August and early September, although there have been no similar incidents since.
The Fifth Fleet said the Iranian seizure was at least the fifth commercial vessel taken by Tehran in the past two years.