Ukraine struck an oil depot in the Russian border region of Belgorod on Tuesday, setting at least one fuel tank ablaze, a military intelligence source in Kyiv told AFP.

Kyiv has ramped up drone attacks on Russia's energy industry in the past three months, terming it "fair" retaliation on infrastructure Moscow uses to fuel its invasion.

A Ukrainian drone hit a depot in the Russian village of Dolgoye, about four kilometres (2.5 miles) from the border, the source told AFP.

Belgorod governor Vyacheslav Gladkov said emergency services were dealing with a fire at an "infrastructure facility", but did not mention a drone.

"There were no casualties. Operational and emergency services are working on the site. All circumstances of the incident are being established," he said.

Ukraine targeted other Russian regions on Tuesday.

Ukrainian artillery strikes in the neighbouring region of Kursk sparked a fire at a train station and cut power to a village, the regional governor said.

"The Glushkovo railway station was shelled from the Ukrainian side. A total of nine incoming attacks were counted, there were no casualties," Roman Starovoit said.

"Electricity lines were also damaged. Glushkovo station and the village of Kulbaki were left without power. As soon as it is safe, emergency crews will start restoring it," he added.

Glushkovo is a town of around 5,000 people and located some 10 kilometres (six miles) from the Ukrainian border. Kulbaki is a smaller village nearby.

Ukrainian drones also targeted the Russian city of Voronezh, further inland, prompting authorities to declare an air alert, regional governor Alexander Gusev said.

The Russian defence ministry said air defences had downed three drones over the border region of Belgorod overnight and one drone over the Kursk region in the morning.