Ukraine’s security service released footage Wednesday of its attack on Russian war planes at multiple airbases across the country. In the span of a few hours on Sunday, nearly a third of Moscow’s strategic bomber fleet was destroyed or damaged with cheaply made drones sneaked into Russian territory, according to Ukrainian officials.

Russia claimed Sunday that its forces are for the first time pushing into the central Ukrainian region of Dnipropetrovsk, an area it has been trying to reach for months, in a move that could create new problems for Kyiv’s much-stretched forces.