A British-flagged oil tanker has been seized by Iran’s Revolutionary Guard as tensions in the Middle East continue to rise, according to reports from the Iranian media and other outlets. Later Friday, news broke about a second tanker, the Mesdar, being seized by Iran, this one flying a Liberian flag.

The owners of the ship, the Stena Impero, say they have been unable to contact the vessel, which was reportedly heading for Saudi Arabia but is now “heading north toward Iran.”

There are reportedly 23 personnel on board the Stena Impero, which was approached by “unidentified small crafts and a helicopter” in the Strait of Hormuz, a hotly contested waterway where a third of the world’s oil supply passes through.

Strait of Hormuz oil Iran

Iran state media confirmed the Revolutionary Guard has “captured a British tanker in the Persian Gulf,” and that the ship was “violating international regulations.”

The news comes on the heels of Britain seizing an Iranian tanker, the Grace 1, earlier this month, reportedly for smuggling oil. Iran of course promised to retaliate for the seizure.

U.S. President Donald Trump weighed in, hailing a “close alliance” with Britain.

“We have a very close alliance with the United Kingdom. We always have,” he told reporters at the White House.

Trump also said the latest incident proves him right about Iran.

“This only goes to show what I’m saying about Iran. Trouble. Nothing but trouble,” he said. “It goes to show you I was right about Iran.”

The news sent the price of oil rising, with West Texas Intermediate up 1% to $55.98 just before the close.

A statement from Northern Marine Managment, which owns the Stena Impero:

2019-07-19 – 19.55

Stena Bulk and Northern Marine Management can confirm that at approximately 1600 BST on 19th July UK registered vessel Stena Impero (built 2018, 49,683 DWT) was approached by unidentified small crafts and a helicopter during transit of the Strait of Hormuz while the vessel was in international waters. We are presently unable to contact the vessel which is now heading north towards Iran.

There are 23 seafarers aboard. There have been no reported injuries and their safety is of primary concern to both owners and managers. The priority of both vessel owner Stena Bulk and ship manager Northern Marine Management is the safety and welfare of the crew.

Northern Marine Management has not been able to establish contact directly with the vessel since it was notified of the incident at approximately 1600 Today, 19th July 2019.

We are in close contact with UK government authorities.