An explosion and subsequent fire occurred at a gas export terminal near St. Petersburg, Russia, on Sunday.

The blast caused a large fire, but it was contained and there were no reported injuries, according to local sources.

The cause of the fire is not yet known, but local media reported seeing drones in the area before the explosion. Ukrainian media sources claimed that Ukraine was behind the attack, but Ukraine has not officially commented.

Both Russia and Ukraine have used drones in the ongoing conflict. Russia launched its full-scale invasion of Ukraine nearly two years ago, but has made little progress in recent months.

Following the incident, a "high alert regime" was put in place at the terminal, which is owned by gas producer Novatek. Novatek announced that work at the terminal had been suspended and said the fire was the result of "external influence."

Local residents reported hearing a drone followed by several explosions, and news outlets reported seeing drones flying in the area before the fire broke out. There were three large international tankers near the fire, but no reports of damage to them.

Russia's defense ministry said it shot down three Ukrainian drones in Smolensk Region, close to its border with Ukraine, on Saturday night. It earlier said it had shot down drones over Tula and Oryol, both in western Russia.

The cause of the explosion and fire at the gas export terminal is still under investigation. It is unclear whether the incident was an accident, a deliberate attack, or something else. The incident is likely to further escalate tensions between Russia and Ukraine. (ILKHA)