The Russian oil tanker Kairos reached its designated anchorage in Burgas Bay at approximately 5:30 p.m. on Monday, concluding a carefully coordinated maritime operation overseen by Bulgarian authorities.
Shortly after arrival, crews began final technical preparations to secure the vessel in place. These included deploying an anchor with the help of a five-ton generator transported aboard a fishing boat, a critical step in stabilising the tanker at its new location.
The relocation marked the end of more than a week of uncertainty after the tanker had remained stationary in waters off the southern coastal town of Ahtopol. Concerns had mounted over navigational safety, environmental risks, and the circumstances that left the vessel stranded.
Earlier in the day, the Kairos began its journey north toward Burgas shortly before 10:00 a.m. The tanker was escorted and pulled by three tugboats, moving slowly along the Black Sea coast under constant supervision.
The operation was technically demanding and time-consuming. Nearly four hours were required to attach the tugboats and manage the vessel’s anchor system before the convoy could proceed safely toward Burgas Bay.
The entire manoeuvre has been overseen by the Executive Agency Maritime Administration, which coordinated with port authorities and other state institutions. Officials said the operation was expected to conclude fully later in the evening once all safety checks were completed.
As the tanker was being towed, environmental authorities intensified monitoring of sea water near Ahtopol. The Ministry of Environment and Water confirmed that precautionary measures were put in place to detect any potential pollution linked to the vessel’s movement.
According to the ministry, the Black Sea Basin Directorate has been conducting continuous water quality checks in coordination with the Regional Laboratory in Burgas since Monday morning.
Samples have been analysed for a range of indicators, including petroleum products, polychlorinated biphenyls, benzene, ethylbenzene, toluene, styrene and fats. These substances are commonly associated with fuel leaks or industrial contamination.
Initial and follow-up analyses carried out after the incident showed no signs of oil pollution or other hazardous substances. All measured values were reported to be well below established safety thresholds.
Authorities said enhanced surveillance of Black Sea waters would remain in place as a precaution. They also assured the public that any deterioration in water quality would be communicated immediately.
The Kairos had been anchored near Ahtopol for around ten days before its relocation. The vessel, sailing under the Gambian flag, is owned by a Chinese company and has been identified as part of Russia’s so-called “shadow fleet”.
There were ten crew members on board at the time of the incident. No injuries or medical emergencies were reported during the period the tanker remained stranded off the Bulgarian coast.
The situation began on December 5, when the Turkish tugboat Timur Bey, which had been towing the tanker, detached from it within Bulgarian territorial waters and returned south, leaving the Kairos without assistance.
The incident prompted diplomatic engagement between Sofia and Ankara. Bulgaria’s Foreign Minister Georg Georgiev and Transport and Communications Minister Grozdan Karadjov summoned Turkey’s Ambassador to Bulgaria, Mehmet Uyanik, seeking clarification.
According to Bulgarian officials, the ambassador stated that the towing operation had been carried out by a private Turkish company without prior notification to Turkish state authorities.
He added that relevant institutions in Turkey had launched an internal investigation and would provide the Bulgarian side with comprehensive information once it became available.
For now, Bulgarian authorities say the immediate risks have been contained. However, questions remain over how the tanker was allowed to drift unchecked for days and whether stricter regional coordination is needed to prevent similar incidents in the future.