Ukraine has evidence that Russia is using Iranian-made Shahed-136 drones as part of its attack – although Iran has denied sending drones to Kremlin forces.
The first use of the drones against Ukraine was recorded on September 13, targeting civilian infrastructure including homes, playgrounds, bridges and schools.
The Shahed-136 drones (kamikaze drones) are small aerial weapons, also known as loitering munitions, which are destroyed after striking the target.
Unlike other drones – which are supposed to return home after dropping missiles – kamikaze drones are disposable.
The name derives from the Japanese pilots who volunteered to crash their planes in suicide missions in World War Two.