Ukraine’s drone attack against Russian airfields was audacious and daring. But most of all, it was meticulously planned and flawlessly executed.

Ukraine unleashed more than a hundred drones smuggled deep into Russia in what it called its most damaging attack yet.

The covert operation was described as one for the “history books” by Ukraine’s president. According to Ukrainian officials, nearly a third of Moscow’s strategic bomber fleet was destroyed or damaged with cheaply made drones sneaked into Russian territory in the span of a few hours on Sunday.