Greece's examines mystery naval drone found in Ionian Sea

The Greek military is examining a mysterious unmanned naval drone spotted in the Ionian Sea by local fishermen.

They found the vessel in a cave near the island of Lefkada on Thursday and alerted the coast guard, which then towed it to the nearby port of Vasiliki. The Greek defence ministry is now overseeing the investigation.

Reports in Greek media say the drone carried explosives and its engine was still running when it was discovered. The reports also suggest vessel could be either Ukrainian-made or linked to the ongoing Russia-Ukraine war.

The BBC has approached both Greece's and Ukraine's military for official comment.

Footage on social media has emerged showing a Greek coast guard boat towing the several metre-long drone to the port.

The dark-coloured drone has its top hatch open. No visible markings can be seen in the video that might help identify the origin of the vessel.

Greek military experts will look at establishing the drone's possible purpose and whether it ended up in Greek territorial waters owing to a technical failure, or the loss of communication with its control centre.

One reported version is that the drone could have been prepared against Russia's "shadow fleet" - a term that refers to hundreds of tankers transporting Moscow's oil and gas to bypass Western sanctions imposed after its full-scale invasion of Ukraine in 2022.

Greece's Ta Nea newspaper says the vessel resembles Ukraine's MAGURA V5 drone, that has been used effectively a number of times. This claim has not been independently verified.

Ukrainian sea drones have revolutionised naval warfare since Moscow's invasion, relentlessly hunting down Russian warships and tankers in the open sea and even at naval bases.

Footage verified by the BBC showed waterborne drones speeding through the waves into the vessels, before detonating into a ball of flame, sending black smoke into the air.

In March, Moscow accused Ukraine of hitting a sanctioned Russian tanker loaded with liquefied natural gas tanker with "uncrewed sea drones" in the Mediterranean Sea between Libya and Malta.

Ukraine's military has not commented on reports that it was responsible for that attack, thousands of miles from Ukraine's coast.