Debris from a downed Ukrainian drone damaged an unused reservoir at a fuel depot in Russia's Voronezh region on Friday, regional governor Alexander Gusev said on the Telegram messaging app.

There were no casualties or fire, and the drone was one of six downed by air defences over the region, he added.

Separately, the RIA news agency cited Russia's defence ministry as saying that 70 Ukrainian drones have been downed overnight over the Rostov region, and 17 over other regions, including the Voronezh one.