Ukrainian drone strikes killed at least eight people in Russian regions overnight and on Sunday, hitting targets including a warehouse belonging to Wildberries, Russia's largest online retailer, regional officials said.
Russia's Defence Ministry said it had downed 635 Ukrainian drones during the night.
Kyiv's drones attacked a Wildberries warehouse in the Samara region, around 800 km (500 miles) from Ukraine's most advanced military positions, Samara Governor Vyacheslav Fedorishchev said. He said there were no casualties and that a fire that had broken out as a result of the attack was being put out.
Ukrainian forces have been striking deeper inside Russia as they expand strikes on economic and energy targets, hoping to undermine Moscow's ability to wage its more than four-year-old war in Ukraine.
They have attacked about a dozen Wildberries sites since July 18 in a bid to disrupt the operations of the company, a linchpin of the consumer economy often described as Russia's answer to Amazon.
A strike on a residential building in the neighbouring Saratov region, meanwhile, killed two people in the city of Engels, Governor Roman Busargin said. Civil infrastructure was damaged both in Engels and in the city of Saratov, he said.
Both Saratov city, which hosts a major oil refinery, and Engels, home of a military airbase, have come under repeated Ukrainian attack in recent years.
Kyiv's military said on Sunday that Ukrainian forces had attacked the Saratov refinery and the Engels airbase, sparking fires at both facilities. It said its forces had also struck an oil depot in the western Kaluga region.
Three people were killed and two injured in a drone attack on the Udmurtia region of Russia, acting governor Olga Abramova said. In the border region of Belgorod, three people were killed and five injured in Ukrainian strikes, the local task force reported.
The governor of Russia's Bashkortostan region, Radiy Khabirov, said that air defence units had repelled a massive drone attack on industrial facilities. One of the drones was shot down over the industrial area of the regional capital of Ufa and a fire was being put out, he said.

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