• The strike sent a ball of flame and black smoke straight into the sky
  • The incident prompted the suspension of operations at the refinery
  • There was another attack, which targeted crude oil reservoirs

Mysterious drones hit a major Russian oil refinery in Novoshakhtinsk in the Rostov region, which is near the border with Ukraine, the plant’s management said Wednesday.

The incident came as the fight between Ukraine and Russia is about to enter its fifth month.

The strike sent a ball of flame and black smoke straight into the sky, prompting the suspension of operations, the authorities told local media. A video was shared on the Telegram messaging service, showing a twin-boom tail configured drone crashing into the Russian oil refinery. There are speculations it was a "kamikaze" drone strike conducted by the Ukrainian Armed Forces, according to the Drive. However, there is no confirmation on the identity of the drone.

International Business Times could not independently verify the authenticity of the video footage.

There was reportedly another attack, which targeted crude oil reservoirs, but it did not cause any fire, according to plant management. No one was reported injured in the incident.

Since Russia invaded Ukraine on Feb. 24, several regions bordering the latter have reported attacks and shelling. The refinery, which was hit Wednesday, is in southwestern Russia, just 5 miles from the border with Ukraine.

“As a result of terrorist actions from the Western border of the Rostov region, two unmanned aerial vehicles struck at the technological facilities of Novoshakhtinsk,” a statement from the plant said, according to Al Jazeera. “Staff have been evacuated and technological equipment has been stopped to assess the damage.”

Ukrainian officials are yet to comment on the alleged attack.

Following the incident, Rostov’s Gov. Vasily Golubev said fragments of two drones had been found at the refinery.

As the war in Ukraine completes its fourth month, Russian forces slowly started advancing in the eastern Donbas region, despite fierce resistance from Kyiv's military. Explosions were also heard in Ukraine's southern city of Mykolaiv on Thursday, Mayor Oleksandr Senkevych said. He urged residents to take shelter, fearing more attacks.

The Russian military currently controls about 95% of the Luhansk region, after struggling for weeks to overrun it completely. Meanwhile, at least 15 people were killed Wednesday as Russian forces pounded Ukraine's second largest city Kharkiv and surrounding countryside with rockets.

A Bayraktar TB2 unmanned combat aerial vehicle is seen during a demonstration flight at Teknofest aerospace and technology festival in Baku, Azerbaijan May 27, 2022. Reuters / AZIZ KARIMOV