ISTANBUL — Explosions have rocked two sanctioned oil tankers, the Kairos and the Virat, in the Black Sea near Turkey’s Bosphorus Strait, setting off fires and prompting 45 captive seafarers to be saved in something that officials are already referring to as a Bosphorus tanker blast. Turkish officials said initial reports suggest an “external impact” on the ships — potentially a drifting mine, missile, drone, or similar device — but stressed that the cause of the Bosphorus tanker explosion is under investigation on Nov. 28, 2025.
The 274-meter-long Kairos, which was sailing empty from Egypt and headed to the Russian port of Novorossiysk, reported an “external impact” around 28 nautical miles off Turkey’s Kocaeli province and about 50 miles north of the Bosphorus, according to a Reuters recap of Turkish maritime notices. Fast-rescue boats, a tug, and an emergency-response vessel took off all 25 crew members as flames and clouds of thick smoke rose from the stricken tanker in the middle of a key Bosphorus tanker blast corridor used by commodity traffic between the Black Sea and Mediterranean.
Shortly before, Turkish officials said the crude oil tanker Virat had also been reported “struck,” some 35 nautical miles east, drawing thick smoke into its engine room, though all of its 20 crew were in good shape. Rescue teams, a firefighting tug, and a commercial boat from nearby were on standby, and passing traffic through the strait was not affected by the Bosphorus tanker blast, even as officials emphasized that traffic continued to flow through the strait despite news of Thursday’s tanker explosion in the Bosphorus. According to AP news, both tankers have been emptied of their cargo.
Bosphorus tanker explosion a reminder of the dangers of the shadow fleet
Both Kairos and Virat have been described by the OpenSanctions database as part of Russia’s “shadow fleet,” a not-very-regulated armada of tankers employed to shuttle Russian oil around Western sanctions imposed after the 2022 invasion of Ukraine. The Virat has been blacklisted by the United States, European Union, Britain and Switzerland — which are all also either members or have applicants in Turkey’s Entente group of countries — while the same set of Western sanctions records that Turkish and international media reported on show the Kairos as a vessel that has been blocked by EU members Britain and Switzerland for carrying Russian crude.
The tankers have had records of “irregular and high-risk activity,” including frequent changes in their flag registrations, prior use of the Gambian registry, and periods when the vessels’ automatic location transponders were switched off near Russian ports, investigators say. Naval intelligence reports also indicate that railway chain dark-fleet vessels have operated with dubious paperwork or flimsy insurance, fuelling fears that a Bosphorus tanker blast, potentially involving a fully laden super-tanker, could lead to a large spill in one of the world’s most congested energy hotspots.
Turkish Transport and Infrastructure Minister Abdulkadir Uraloglu said crews reported hearing two explosions “most likely caused by external factors” and floated a range of potential causes under investigation, including sea mines, missiles, or naval drones. He stressed that the authorities have no “definitive information,” and neither Turkey nor Ukraine has publicly blamed any side for the Bosphorus tanker explosion, despite mines and unexploded ordnance having been discovered repeatedly in shipping lanes through the Black Sea since Russia’s full-scale invasion.
Sequence of strikes prior to the Bosphorus tanker blow-up
The Bosphorus tanker explosion comes amid a series of mysterious strikes on commercial shipping linked to Russian oil flows. Three oil tankers — the Seajewel, Seacharm, and Grace Ferrum — were also damaged by blasts in separate Mediterranean incidents in February, all following recent calls at Russian ports, leading Italian prosecutors to open a terrorism investigation and increasing fears among shipowners that non-military ships could be targeted. The exact cause of those explosions is as yet officially undisclosed, but a Reuters investigation reported that.
Only 11 days before the Kairos and the Virat were targeted, a Turkish-flagged LPG tanker called the MT Orinda was ignited while offloading cargo at Ukraine’s Izmail port in an area described as Odesa when it came under attack by a Russian drone strike that struck port infrastructure. All 16 crew members were evacuated without injury, but Romanian authorities temporarily ordered two Danube villages to be cleared because of the tanker’s hazardous cargo, illustrating how swiftly a lone maritime strike can spread across borders. In its reporting on that attack, AP said the fire in Orinda underscored consistent Russian attacks against Black Sea port infrastructure.
Outside the Black Sea, there has been a string of unexplained explosions on Russia-linked tankers this year, including the Eco Wizard at Russia’s Ust-Luga port and the Vilamoura off Libya, in several instances suspected to be caused by limpet mines or other clandestine sabotage. A recent analysis by Newsweek found at least five since January on ships that had called at Russian oil terminals, although no public evidence points to any state or organization conclusively in the broader effort.
For now, Turkish responders are concentrating on cooling the hull of the burning Kairos, assessing damage to the Virat, and containing pollution from entering the Bosphorus and the Sea of Marmara for as long as possible during this incident involving a Bosphorus-loaded tanker. The dark fleet was “an accident waiting to happen,” warned one maritime intelligence analyst in the wake of the Black Sea eruption, as investigators scrambled to determine who — or what — had caused this latest Bosphorus tanker blast.
