Russia and Ukraine have apparently been intensifying drone attacks against each other.
Ukraine's air force said on Sunday that it destroyed 26 out of 33 drones launched from Russian territory targeting the capital Kyiv.
Authorities in Kyiv said debris from the downed drones fell over residential buildings, leaving one person injured.
Russia's defense ministry on Sunday said its forces shot down eight Ukraine-launched drones over the sea near Crimea. The region in southern Ukraine was unilaterally annexed by Russia in 2014.
The ministry also said its forces destroyed a drone over the western region of Bryansk, which borders Ukraine.
Britain's defense ministry said on Sunday that the governor of the Pskov region in Russia has organized volunteer security patrols to defend an air base there. In late August, transport aircraft were reportedly damaged by drone attacks on the base.
The ministry says up to 800 citizens have reportedly signed up to join the patrols, which will consist of groups of 50 divided among multiple municipalities.
It says they will patrol border areas and critical infrastructure, particularly airports and airbases.
The ministry says, "The use of volunteers highly likely indicates a shortage of trained security personnel within Russia."