The French Navy said on Tuesday that authorities were investigating a possible infraction by the oil tanker Boracay, a vessel suspected of belonging to the so-called "shadow fleet" involved in the Russian oil trade.
The vessel is listed under British and European Union sanctions against Russia. It was detained by Estonian authorities earlier this year for sailing without a valid country flag.
"Shadow fleet" tankers typically have opaque ownership and insurance and are often more than 20 years old.
The crude oil tanker left the Russian port of Primorsk on September 20, according to MarineTraffic data. It sailed through the Baltic Sea and over the top of Denmark before entering the North Sea and transiting west through the Channel.
Ship tracking data shows that the 2007-built tanker was being shadowed by a French warship after it rounded France's northwestern tip, before altering course and heading east towards the French coast. It is currently at anchor near Saint Nazaire.
The French Navy said an investigation was underway. The Brest prosecutor told Reuters a probe had been opened after the crew failed to provide proof of the vessel's nationality and failed to comply with orders.
Britain and the EU imposed separate sanctions on the crude oil tanker in October 2024 and February 2025.
The EU said the vessel was linked to the transport of Russian crude oil and petroleum products, "while practising irregular and high-risk shipping practices".
The UK said the vessel was, "involved in activity whose object or effect is to destabilise Ukraine…or to obtain a benefit from or support the government of Russia," in the transport of oil or oil products that originated in Russia from Russia to a third country.
The vessel, which changed its name to Boracay or on some shipping databases Pushpa in December 2024 was previously named Kiwala. Ships keep the same IMO identification number throughout their lives but do change names.
(Reporting by Gabriel Stargardter in Paris and Jonathan Saul in London; Editing by Richard Lough and Ed Osmond)
