Last week, commandos of Iran’s Navy of the Islamic Revolutionary Guard Corps stormed two British tankers that were sailing in the Strait of Hormuz. The aggressive seizure of the two ships was in response to the previous detainment of an Iranian tanker by British Royal Marines. That ship was illegally carrying oil to Syria in violation of internationally imposed sanctions.

Speaking about the connection between the two incidents, British Foreign Secretary Jeremy Hunt stated, “Grace 1 [the Iranian tanker] was detained legally in Gibraltarian waters because it was carrying oil, against EU sanctions, to Syria, and that’s why the Gibraltarian authorities acted totally with respect to due process and totally within the law. Stena Impero [one of the two U.K. tankers] was seized in Omani waters in clear contravention of international law; it was then forced to sail into Iran. This is totally and utterly unacceptable. It raises very serious questions about the security of British shipping, and indeed international shipping, in the Strait of Hormuz.”

The second British tanker, Mesdar, which was flying under a Liberian flag, was only boarded for a few hours before the Iranians departed.

In a video released by the Iranian military, the Iranian commandos are seen fast-roping onto the deck of the unarmed ship. Although the tanker’s crew posed no danger to the Iranian commandos, the operation as a whole was inherently dangerous by its very nature. The tanker, though it appears static, is sailing, thereby making the fast-rope component quite difficult. In order to safely land his passengers on the deck, the Iranian helicopter pilot had to maintain enough forward speed to keep the chopper as steady as possible. The fact that the tanker was moving further complicated the operation and showcased the expertise of the Iranian crew. Never underestimate your enemies.