An oil tanker that was struck by Ukrainian drones near Turkey November 28 had to be rescued in bad weather about a mile off the coast of Bulgaria, the Balkan nation’s maritime authority said December 5.

The Kairos, which was hit on November 28 is being assisted by Bulgaria’s Maritime Administration Agency, along with naval and police forces, the country’s Ministry of Transportation and Communications said in a statement. 

It’s unclear how the vessel got there, but the MAA said the ship was under constant surveillance as a result of strong waves and bad weather in the area. The 900-foot tanker doesn’t have a cargo on board, and images released by Turkish authorities last week showed a significant blaze on the ship at the time of the strike, likely to be caused by the fuel that powers its engines. 

The ship didn’t respond to requests to contact it when entering Bulgarian waters, but later issued a request for evacuation. Ten people were on board at the time. Turkish authorities said last week that 25 personnel had been removed from the ship at the time of the strike.

“Two tugboats are also fully prepared to join the operation,” the MAA said in its statement. “The services continue their actions to provide assistance and secure the situation. The adverse weather conditions in the area greatly complicate maneuvering and rescue operations.”

Sea Baby naval drones operated by the Security Service of Ukraine carried out the attacks, a person familiar with the operation, who declined to be identified because the information isn’t public, told Bloomberg on November 29. The strike happened a day earlier.