Ukrainian authorities have begun mass evacuations of communities in the country's northern Sumy region close to the Russian border after extended periods of intense shelling of the area, local officials said on Friday.

The military administration of Sumy region, writing on the Telegram messaging app, said more than 180 residents of areas near the Velikopysarska community, next to the border, had been evacuated over the past three days.

Authorities in Sumy have long been issuing daily reports of Russian shelling, but the attacks have intensified.

The regional administration said the areas in question were "the most tense" in Sumy region, with three people killed and 13 wounded over the past five days.

The administration said a total of more than 4,500 residents had been evacuated from 22 villages in Sumy region, but gave no time frame.

Velikopysarska is located a few kilometres from the village of Kozinka across the border in Russia - where local authorities this week said an incursion by armed groups caused considerable damage. The groups described themselves as being made up of Russians opposed to the Kremlin and said they were conducting a military operation in the area.

The governor of Belgorod region, Vyacheslav Gladkov, said shelling of areas under his jurisdiction continued on Thursday, with one person injured. Gladkov toured border areas late on

Wednesday and said there were no enemy forces in the region.

The governor of the neighbouring Russian region of Kursk, Roman Starovoit, said air defence units had downed three Ukrainian drones on Thursday night.