(Reuters) -A Ukrainian drone attack damaged an industrial facility in Russia's southern region of Saratov, its governor said early on Tuesday, while a Ukrainian official said an oil refinery had been hit.
"There are no casualties," Roman Busargin, the governor of Saratov, said in a post on the Telegram messaging app, citing initial details, but without identifying the damaged facility.
Russia's defence ministry said its air defences destroyed 40 Ukrainian drones overnight, 18 of them over Saratov.
As a safety measure, the aviation watchdog Rosaviatsia said it was suspending flights at the regional airport as well as those in Kazan, Ulyanovsk and Kirov.
Ukrainian Lieutenant Andriy Kovalenko, an official of the National Security and Defense Council, said the Saratov oil refinery that supplies the Russian army with fuel was hit.
But Kovalenko, who heads the council's Center for Countering Disinformation, did not directly say that it was the result of a Ukrainian attack.
Russian media say the Saratov oil refinery belongs to oil major Rosneft.
Several unofficial Russian news channels on Telegram, including the Shot channel, reported explosions and fires around the refinery.
A large fire sent thick billows of smoke into the night sky, in video clips and photographs posted on social media. Reuters could not independently verify the reports, however.
Kyiv has often said its air attacks inside Russia aim at destroying infrastructure key to Moscow's war efforts and are in response to Russia's continued attacks on Ukraine since the start of the war nearly three years ago.
In January, a Ukrainian attack on an oil depot near a military air base in Engels in the Saratov region sparked a fire that took days to be put out.
(Reporting by Lidia Kelly in Melbourne; Editing by Christian Schmollinger and Clarence Fernandez)
