A Ukrainian drone attack killed a mother and her toddler in western Russia on Wednesday, local officials said, in a major overnight barrage that set an oil refinery ablaze and targeted a nuclear facility.

Russia’s air defences reportedly destroyed drones over nine regions, including 11 over Smolensk, which sits on the border with Belarus. Nearly half were hit over Kursk, where Ukrainian troops have occupied several villages for months following an incursion.

A series of drone strikes have hit parts of Russia, with oil refineries and power infrastructure targeted in the west of the country, according to regional officials