The same data networks that enable phone apps and web surfing help drones navigate, so officials are imposing daily, patchwork shutdowns. The actions can be very disruptive to daily life.

Five people have been killed in overnight strikes in Russia and Ukraine, as the two sides continue to trade drone attacks. Ukrainian officials said on Saturday that more than 200 drones and almost 30 missiles were fired by Russia, with most targeting Dnipropetrovsk where three people died.