Estonia’s foreign minister said Thursday that a Russian military jet was deployed as the Estonian Navy attempted to intercept a Russia-bound oil tanker, the Jaguar, which had been placed under British sanctions and was accused of sailing without a flag.

The incident unfolded near Naissaar Island, off the coast of Tallinn, where Estonian forces identified the Jaguar as part of Russia’s so-called "shadow fleet," a term Western governments use to describe vessels allegedly used by Moscow to bypass international sanctions.

Estonian Foreign Minister Margus Tsahkna stated in Antalya, Turkey, ahead of a NATO foreign ministers' meeting, that the Russian Federation sent a fighter jet to "check the situation," adding, "We need to understand that Russia has officially tried and connected itself to the Russian ‘shadow fleet’."

He added, "The Russian Federation is ready to protect the ‘shadow fleet’... The situation is really serious," calling for faster and tougher sanctions against Moscow.

The Jaguar was added to the UK sanctions list last Friday.

When contacted by the Estonian Navy at 15:30 GMT on Tuesday, the vessel refused to comply with a boarding attempt. According to the Estonian Navy, the operation was carried out under legal obligations to verify the ship’s documentation and status, as it appeared to be sailing without a recognized nationality.

Commander Ivo Vark of the Estonian Navy said, "The vessel denied cooperation and continued its journey toward Russia... Given the vessel's lack of nationality, the use of force, including boarding the vessel, was deemed unnecessary."

According to reports, the vessel was then escorted to Russian waters. Moreover, marine traffic data on Thursday showed the Jaguar anchored near the Russian port of Primorsk, listed under the flag of Gabon.

NATO response and air patrol deployment

According to the report, the deployment of the Russian jet triggered a response from NATO, with military aircraft based in the Baltic taking off to monitor the situation. 

A video, which circulated on social media, showed Estonian naval vessels, a helicopter, and a patrol aircraft surrounding the Jaguar. A voice can be heard in English commanding, "This is Estonian warship... follow my instructions, alter your course to 105 immediately."

A Russian speaker responds, noting that helicopters are demanding the ship's anchor.

Estonia has not confirmed if this incident is related to a previously reported "airspace breach" involving a Russian Su-35 jet earlier in the week, which prompted a diplomatic protest from Tallinn.

Margarita Simonyan, head of Russia’s state media outlet RT, claimed the Su-35 was dispatched to prevent the Jaguar’s seizure.

The incident comes after Estonia detained another Russia-bound oil tanker, Kiwala, on April 11, also allegedly sailing without a valid flag. 

Western governments have said Russia’s shadow fleet is central to maintaining its oil exports despite sanctions. That said, Britain asserts that sanctioning these vessels limits Russian President Vladimir Putin’s ability to finance the war in Ukraine.