Ukraine launched a new wave of drone strikes on Russia’s border regions of Kursk and Kaluga overnight, according to the Russian defence ministry.
At least one drone targeted a power substation, Russian officials said, blowing up a transformer and cutting power supplies to the village of Belaya, less than 25km from the border.
Kyiv is yet to comment on the attacks, which began on Thursday evening and continued into Friday morning, and does not typically claim responsibility for operations across the border in Russia.
Russia’s defence ministry said it shot down at least 10 drones over Kursk and one over Kaluga, according to an official quoted in state media.
Drone attacks by both sides have increased in recent months on Moscow, the border regions, and on Crimea, which Russia illegally annexed from Ukraine in 2014.
Russia claimed the power cut to Belaya affected a hospital. Regional governer Roman Starovoyt said on Telegram that one of the power substation’s transformers was destroyed by explosive devices dropped by a drone.
"Five settlements and a hospital were cut off from power supply. Fire crews rushed to the scene," he said, according to AFP.
"Power will be restored as soon as it is safe to do so."
The Russian defence ministry earlier said it downed two Ukrainian drones over the neighbouring Belgorod region. The first drone was reportedly "thwarted" at about 5pm (local time) on Thursday, while a second one was brought down around four hours later.
"The Ukrainian unmanned aerial vehicle was destroyed over the Belgorod region by air defence systems on duty," the ministry said.
Meanwhile, three women were killed in the street after artillery hit a residential area in Kherson, Ukraine’s internal affairs minister Ihor Klymenko said on Thursday. Two men were killed in another Russian attack on Krasnohorivka.
A further three people were injured, with three more injuries sustained by further shelling nearby in Kostyantynivka.
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