(Reuters) - Ukraine launched drones on several Russian regions in hours leading to Wednesday morning, Russian officials said, with unofficial Russian news outlets reporting a fire at the Ryazan oil refinery after the attack.

Pavel Malkov, governor or the Ryazan region, which shares a border with the Moscow region in its northwestern parts, said that there were no injuries in the drone attacks there.

Russian Telegram channel Baza, which is close to the security services, reported that the attack sparked a fire at the Ryazan oil refinery.

The refinery, owned and run by Rosneft, refines about 5.8% of Russia's total refined crude. It has been a frequent target for Ukraine's air attacks.

The governors of the Kursk and Voronezh regions in southwest Russia that border Ukraine also reported drone attacks on their territories, saying there was no damage or injuries.

Russia rarely discloses information about the full impact of Ukraine's attacks on its territory and infrastructure.

Kyiv officials say targeting Russia's military, energy and transport infrastructure undermines Moscow's war effort.

Reuters could not independently verify the Russian reports.

(Reporting by Lidia Kelly in Lisbon; Editing by Kim Coghill)