The Russian armed forces say dozens of Ukrainian drones were repelled during the night in regions close to the border, while a British analysis suggested Moscow's forces also shot down one of their own combat jets last month.
A total of 31 unmanned aerial vehicles were intercepted by air defence forces over the Belgorod, Bryansk and Kursk regions, the Defence Ministry in Moscow said on Wednesday morning.
Belgorod Governor Vyacheslav Gladkov spoke of damage to an administrative building.
Russia launched a full-scale invasion of Ukraine more than 19 months ago.
Attacks on Russian territory have been increasing recently although Moscow often downplays their impact. However, the extent of the damage and number of victims bear no relation to the consequences of the war in embattled Ukraine.
British analysts said that Russian air defences had accidentally shot down a Russian fighter jet, near the occupied town of Tokmak in southern Ukraine.
"On 28 September 2023, Russian air defence forces highly likely shot down one of their own Su-35S FLANKER M multi-role combat jets over Tokmak, approximately 20km behind the current front line," the British Ministry of Defence said in its daily update.
Although Russia has lost around 90 fixed wing aircraft since the start of the invasion, this is probably only the fifth loss of a Su-35S, Russia's most advanced combat jet in widespread service, the analysis said.
"The location is relevant because Tokmak is a heavily fortified town which often hosts Russian headquarters commanding one of the most intensely contested sectors of the front line," according to the analysis shared on X, the platform formerly known as Twitter.
"These headquarters would typically be protected with dedicated short and medium range air defence systems. These are almost certainly held at very high readiness, as Ukraine continues to conduct effective deep strikes against such locations."
