Russia has been using drones and missiles to strike targets, wait some time, and then hit the same spot later.

Ukraine said Saturday it struck an airbase in Russia, which continued overnight to use hundreds of drones in its stepped-up bombing campaign. The fresh wave of attacks signal a breakthrough isn't expected anytime soon in efforts to end the more than three-year-old war.

Russia launched 550 drones and missiles across Ukraine overnight in the largest aerial assault since the war began. The capital Kyiv was the primary target.