Kyiv/Moscow, May 1 (IANS/DPA) Ukrainian drones have damaged a refinery in Ryazan, some 200 kilometres south-east of Moscow, an unnamed representative of the Ukrainian military intelligence service HUR told the Ukrainska Pravda website.

"A military target in Ryazan was hit. There is considerable damage," the website reported. Independent Russian media reported a fire at the Ryazan refinery.

The second target was an oil processing plant in the Russian region of Voronezh. The intelligence service did not officially confirm the information, but the Ukrainian press is informed of such attacks in secret.

The Russian Ministry of Defence in Moscow announced that Ukrainian combat drones had been intercepted during the night over the Russian regions of Voronezh, Ryazan, Belgorod and Kursk.

The Ukrainian armed forces have further developed their drones and have been attacking refineries far into the Russian hinterland for several weeks. The aim is to disrupt the fuel supply for the Russian army.

The US has criticised these attacks because it fears an impact on world oil prices. However, Kyiv is sticking to this tactic. Ukraine has been fending off a large-scale Russian invasion for more than two years.

On Wednesday, the eastern Ukrainian city of Kharkiv was hit by several glide bombs fired by Russian aircraft from a safe distance. The governor there, Oleh Syniehubov, reported at least three deaths.

Overnight, Russia fired missiles at the Ukrainian port city of Odesa on the Black Sea. According to regional governor Oleh Kiper, three people were killed and three others injured.