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.

Recent Russia-Ukraine peace talks in Istanbul on June 2nd yielded only minor humanitarian agreements on prisoner exchanges and the repatriation of fallen soldiers’ remains, with no progress towards a ceasefire.