Greek authorities are conducting a widening investigation into how an explosive-packed naval drone came to rest in the waters off Lefkada, a popular resort island in the Ionian Sea on Greece's western coast. The unmanned vessel was discovered last Thursday by a fisherman inside a cave, its engine still running. Bomb disposal experts subsequently removed its detonators and battery before conducting a controlled explosion at sea near the port of Astakos. Military teams have since transported the remains of the drone to a naval base on the mainland for forensic examination.

Specialist investigators are analysing the device's serial number and built-in GPS system to determine its origin. Both Greek and Ukrainian media have identified it as likely a Magura V3, a Ukrainian-made long-range naval drone capable of carrying explosive loads of up to 300 kilograms and travelling for up to 60 hours at roughly 80 kilometres per hour. The drone found near Lefkada is estimated to have been carrying approximately 100 kilograms of explosives. Reports in credible Greek outlets add that handwritten notes in Ukrainian were found aboard the vessel. Ukraine has not officially commented on the incident.

Greek Defence Minister Nikos Dendias said the drone almost certainly originated from "a foreign state," without naming one, and suggested its operators lost control, causing it to drift off course. Two leading theories are under consideration: that the drone fell into the sea while being transported, or that it was targeting Russian oil and gas shipping in the Mediterranean but lost contact with its operators. Ukraine has conducted an extensive drone campaign against vessels in Russia's so-called shadow fleet — tankers used to move sanctioned energy exports — primarily in the Black Sea. In March, Russia accused Ukraine of striking a sanctioned tanker in the Mediterranean between Libya and Malta. Greece and Ukraine signed a joint agreement in November to co-produce naval drones, though reports suggest Kyiv has since sought veto rights over their use in military operations, reportedly out of concern they could be deployed against neighbouring Turkey, with whom Greece has longstanding territorial disputes.

The discovery has sparked sharp political criticism at home. Opposition figures accused the government of being ill-prepared for the threat posed by advanced drone technology, with one opposition defence spokesman warning that Greece risked being drawn into the theatre of war. The Greek Communist Party demanded to know whether Athens had prior knowledge of any operational plan the drone was part of, while the pro-Russian nationalist Hellenic Solution party called the incident a "conscious military provocation." Dendias pushed back against the criticism, insisting Greece was investing in cutting-edge drone and counter-drone capabilities for its navy.

The episode highlights a broader security challenge for Greece, which possesses Europe's longest coastline — making its extensive maritime borders exceptionally difficult to monitor. The incident underscores how the war in Ukraine is increasingly projecting instability into the wider Mediterranean, as drone warfare evolves beyond the Black Sea and into waters shared by EU member states.