PARIS, Oct 2, (AP): French President Emmanuel Macron said Wednesday that an oil tanker immobilized off the French Atlantic coast had committed "very serious wrongdoings” and linked it to Russia’s shadow fleet, which is avoiding Western sanctions over Moscow's war in Ukraine. The tanker was sailing last week off the coast of Denmark and was cited by European naval experts as possibly being involved in drone flights over the country.

French naval forces forcibly boarded the ship a few days ago at the request of prosecutors who suspected wrongdoing, a military official said Wednesday. The prosecutor’s office in the western French city of Brest said a judicial investigation has been opened into the crew’s "refusal to cooperate” and "failure to justify the nationality of the vessel.”

The ship was ordered to stay in place pending further investigation, the military official said. French naval forces boarded the ship again Wednesday to provide food and fuel to the crew aboard, according to the official, who was not authorized to be publicly named discussing an ongoing investigation. The ship left the Russian oil terminal in Primorsk near Saint Petersburg on Sept 20, sailed off the coast of Denmark and has stayed off the coast of the French western port of Saint-Nazaire since Sunday, according to the Marine Traffic monitoring website.

Macron suggested it was stopped by French authorities' "intervention,” saying: "I think it’s a good thing that this work has been done and that we’ve been able to stop it.” "There were some very serious wrongdoings made by this crew, which is why there are legal proceedings in the case,” Macron said on the sidelines of a summit of European Union leaders in Copenhagen, Denmark.

He didn't elaborate. The Russian Embassy in Paris didn't respond to a request for comment. Asked whether the ship was connected to drone incidents in Denmark and about reports that two people aboard had been detained, Danish Prime Minister Mette Frederiksen said she wouldn't comment on specific investigations.

But she added, "I can say in more general terms that we are facing a lot of problems with the shadow fleet. And that has been the case, especially in the Baltic Sea for quite a long time. And we are working very closely together to battle this situation.'' Macron said the incident highlights "the existence and the reality of a phenomenon that we have been describing and denouncing for a long time” that is the "notorious shadow fleet” that represents tens of billions of euros for Russia’s budget and finances an estimated 40% of Russia’s war effort.