British authorities have detained a sanctioned crude oil tanker in a joint operation conducted with French naval forces, marking one of the latest efforts to enforce international sanctions on vessels linked to Russia’s so-called “shadow fleet.” The vessel was intercepted while transiting the English Channel and is currently under investigation by UK authorities.

According to reports, the operation involved British Royal Marines, the National Crime Agency (NCA), and support from French authorities. The tanker was boarded without reported resistance from the crew, and the vessel was subsequently escorted to an anchorage off southern England for further examination.

Authorities allege that the tanker may have been involved in transporting sanctioned Russian oil. Investigators are examining vessel documents, cargo records, and ownership details to determine whether sanctions regulations were violated. The vessel has reportedly been identified as part of a network of ships often referred to as the “shadow fleet,” which has been accused of using various methods to bypass international restrictions on oil trade.