Drone Strike Hits Oil Tanker Near Bosphorus, Raising Risk on Key Shipping Route

By Bosphorus News Defense Desk

A sea-borne drone struck the Turkish operated oil tanker Altura in the Black Sea early on March 26, causing an explosion in the engine room about 18 nautical miles from the Bosphorus Strait. All 27 crew members, all Turkish nationals, were unharmed. No oil spill was detected.

Transport and Infrastructure Minister Abdulkadir Uraloğlu said the blast was deliberate and that the engine room appeared to have been the primary target. "We believe the engine room was specifically targeted," he told 24TV. He also said the device was not an aerial drone but an unmanned surface vehicle operating at or below the water line.

Türkiye's Foreign Ministry said it viewed the attack with "great concern," adding that the strike took place within Türkiye's exclusive economic zone and violated international law. Ankara said it reserved the right to take necessary measures to protect the country's economic interests and was in contact with relevant parties to prevent further escalation. Turkish naval vessels are patrolling the area.

The explosion severely shook the vessel's bridge, disabled navigation equipment and allowed water into the engine room. The coastguard and the emergency response vessel Nene Hatun were dispatched to the scene.

The Vessel

The Altura is a Turkish-operated tanker carrying about 1 million barrels of Urals crude loaded at Russia's Novorossiysk port. The vessel has been placed under European Union and United Kingdom sanctions and is classified as a shadow fleet ship on MarineTraffic.

Strike Zone Moving Toward Istanbul

The strike is the closest such attack to the Bosphorus since the Black Sea tanker campaign began. It also confirms a pattern that became visible in December, when shadow fleet tankers began rerouting closer to Türkiye's coastline after earlier attacks farther east. The shift did not remove the risk. It moved the danger closer to Türkiye's shores.

In November 2025, Ukrainian naval drones struck two shadow fleet tankers, the Kairos and the Virat, inside Türkiye's exclusive economic zone. The Kairos caught fire 28 nautical miles off the Turkish coast and later ran aground in Bulgarian waters. The Virat was hit twice within hours. Türkiye's Foreign Ministry condemned both attacks at the time, warning of serious risks to navigation, life, property and environmental safety.

On March 14, 2026, the Greek-flagged Maran Homer, chartered by U.S. oil company Chevron and sailing to Novorossiysk to load Kazakh oil, was hit 14 nautical miles off the Russian port. The vessel was not part of the shadow fleet. Twelve days later, the Altura was struck near the Bosphorus.

A Laden Tanker at the Strait Entrance

A disabled tanker carrying 1 million barrels of crude 18 nautical miles from the Bosphorus entrance is one of the scenarios Türkiye has long feared. The strait handles about 48,000 vessel transits a year and narrows to roughly 700 metres at its tightest point as it runs through central Istanbul. Türkiye controls military transit through the straits under international treaty, but no existing framework addresses unmanned surface attacks on the approaches.

No oil spilled from the Altura, and the damage was contained. This time, the outcome remained manageable. The margin is getting thinner with each attack.

Broader Energy Pressures

The tanker strike comes as Türkiye's energy supply faces pressure from multiple directions. TurkStream and Blue Stream pipeline infrastructure in southern Russia has been targeted by repeated Ukrainian drone attacks since late February. The Strait of Hormuz remains effectively closed following the U.S.-Israeli strikes on Iran, with Brent crude trading above $109 per barrel.

Erdoğan's Warning, Four Months Later

In December 2025, President Recep Tayyip Erdoğan warned that the Black Sea must not become "an area of confrontation" between Russia and Ukraine. Four months later, a laden tanker has been disabled near the Bosphorus approaches. Neither Moscow nor Kyiv has commented on the attack.

***Ukraine's SBU claimed responsibility for the November 2025 strikes on the Kairos and Virat. No party has claimed responsibility for the Altura attack, and Türkiye has not publicly identified a perpetrator.