Allied aircraft are often scrambled in NATO nations like Poland and Romania in response to Russian long-range attacks in Ukraine, which regularly target locations along Ukraine's border with its NATO neighbors.

Two German fighter jets were sent to the Ukraine-Romania border Tuesday night following a wave of drone strikes from Russia. Oleh Kiper, the head of the Odesa province in Ukraine, said drones hit infrastructure and production facilities in the city of Izmail,

Many of the drones aren’t particularly fast or high-tech, but they are cheap enough for the Kremlin to launch more than 700 in one night, in an effort to overwhelm Ukraine’s air defenses. Here’s what we know.