Bulgaria: Drone Exploded Near Gas Pipeline Supplying Gas to Ukraine

A drone “carrying a significant amount of explosives” exploded in Bulgaria near a compressor station on the Trans-Balkan gas pipeline, which supplies gas, including to Ukraine.

This was reported by the Associated Press, citing Bulgarian Prime Minister Rumen Radev.

According to him, the incident occurred around 5:00 a.m. after the UAV crossed the border from the Romanian side near Kardam and flew about 100 meters into Bulgarian territory.

The drone was neither detected nor identified while flying through the airspace of Romania and Bulgaria.

“There were no casualties or damage to buildings. The area has been cordoned off. We keep monitoring the situation,” Radev stated after an emergency government meeting.

According to the prime minister, the drone exploded approximately 200 meters from a Romanian compressor station and about one kilometer from a Bulgarian compressor station on the Trans-Balkan gas pipeline.

“We will continue to follow the situation and step up surveillance. Following this incident, we will also redeploy border police resources to detect and counter drones from the border with Turkey to the border with Romania,” Radev said.

According to Bulgarian Defense Minister Dimitar Stoyanov, given the force of the explosion and the column of black smoke, the drone was likely carrying a significant amount of explosives.

The Trans-Balkan Gas Pipeline

The Trans-Balkan gas pipeline is a system of main gas pipelines built in the late 1980s to transport Russian natural gas through Ukraine, Moldova, Romania, and Bulgaria to Turkey. Branches of the system also supplied gas to Greece and North Macedonia.

Historically, gas flowed through the Trans-Balkan gas pipeline from north to south. However, following the launch of TurkStream and the cessation of Russian gas transit through Ukraine on January 1, 2025, this direction has lost its former significance.

Currently, the infrastructure is being reoriented for reverse gas transportation from south to north—from Greece through Bulgaria, Romania, and Moldova to Ukraine. The route provides access to liquefied natural gas from Greek terminals, as well as to gas from Azerbaijan, Romania, and the Eastern Mediterranean. The gas pipeline also makes it possible to utilize Ukrainian underground storage facilities to serve the countries of Southeast Europe and Moldova.

In July 2025, Naftogaz Group signed its first agreement with the Azerbaijani company SOCAR to supply gas to Ukraine via this route through Bulgaria and Romania.

As a reminder, in late May, the Romanian Ministry of National Defence, after analyzing the debris, officially confirmed that a Russian Geran-2 (Shahed) strike drone had struck a residential high-rise building in the city of Galați.