Update: A British tanker, as well as a Liberian tanker have been seized.

A British tanker has been seized by the Iranian Revolutionary Guard in the Strait of Hormuz, the organization says.

According to Press TV, the Stena Impero, a Chemical/Oil Products Tanker, was seized “because of violating international regulations.”

The seizure was confirmed by Stena Bulk, the tanker’s owner. It was later confirmed by Northern Marine Management.

Reportedly, the tanker “was approached by unidentified small crafts and helicopter during transit of the Strait of Hormuz while the vessel was in international waters.”

They continued, “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.

“We are in close contact with UK government authorities.”

The ship seizure comes amidst weeks of rising tensions between Iran and the U.S. and its allies, as Iran sought to push back against US sanctions and recommence their uranium enrichment programme.