Families in Ukrainian cities are taking refuge from massive swarms of Russian drones, as Moscow steps up its airborne assault with attacks designed to undermine Ukrainian morale.

Rustam Minnikhanov, the Kremlin-installed head of Tatarstan, told state-run RIA Novosti that one person was killed and another was critically injured when drone debris struck a checkpoint at a local factory.

Ukrainian officials say three people were killed and 13 were wounded when Russia attacked the country with waves of drones and missiles.