This story was updated at 5:30 pm ET
Iran's Revolutionary Guard have seized a British-flagged oil tanker off the Strait of Hormuz, Iranian media reported Friday.
A second tanker, a Liberian-flagged but British-owned ship known as the Mesdar, was reportedly also seized by Iran Friday, prompting a strong statement from UK Foreign Secretary Jeremy Hunt.
“I’m extremely concerned by the seizure of two naval vessels by Iranian authorities in the Strait of Hormuz,” Hunt said in a statement. “These seizures are unacceptable.”
But soon after Hunt's statement, Iranian media reported that the second ship had been let go and was no longer in Iranian waters.
Friday's skirmishes on the Strait of Hormuz mark another escalation in the stand-off between Iran and the west, and come a day after President Trump announced that an American warship shot down an Iranian drone in the same waters. Iranian officials have denied that it was one of their drones.
The tanker still under seizure, named Stena Impero, was captured and guided to shore by Iranian Revolutionary Guard forces, the Iranian Tasnim news agency reported on Friday.
The company that owns the vessel, Stena Bulk, said it has lost contact with the ship sometime after 11:00 am E.T.
The tanker “was approached by unidentified small crafts and a helicopter during transit of the Strait of Hormuz while the vessel was in international waters,” the company said in a statement on its web site. “We are presently unable to contact the vessel which is now heading north towards Iran.”
The company said there are 23 sailors on board, and there have been “no reported injuries.”
“We are in close contact with UK government authorities,” the company said.
None of the sailors on board the ship are believed to be British citizens, Hunt said.
The seizure appears to make good on a promise from a Revolutionary Guards Commander two weeks ago to capture a British ship in response to the seizure of an Iranian tanker called Grace 1 by UK forces in Gibraltar.
“If Britain does not release the Iranian oil tanker, it is the authorities’ duty to seize a British oil tanker,” Mohsen Rezai tweeted. Earlier Friday, Gibraltar announced it would extend the detention of Grace 1 by one month.
The Strait of Hormuz is one of the most strategically important waterways in the world due to its role as a key energy transportation lane, and has become the focal point in Iran’s escalating tensions with the U.S.
Conflict in the area has picked up in recent weeks, after Iran shot down a U.S. spy drone it claimed had crossed into its airspace. The incident brought Trump within minutes of launching a strike against Iran, he claimed, before pulling back at the last moment.
Trump has said the U.S. military was “cocked & loaded to retaliate,” but that he decided not to launch an attack that would kill some 150 Iranians in response to the loss of an unmanned drone.
The U.S. has deployed more forces to the region in recent weeks, including the USS Boxer that was involved in yesterday’s altercation, to help guard commercial ships against Iran’s escalatory actions.
Cover: In this July 2, 2012 file photo, an Iranian Revolutionary Guard speedboat moves in the Persian Gulf while an oil tanker is seen in background. (AP Photo/Vahid Salemi, File)