Ukraine fended off 36 Russian air attacks in and around the capital overnight while pro-Kyiv Russian fighters said they were battling Russian forces for a second day inside Russia, trading blame with Moscow for the deaths of two civilians.

Russia has launched about 20 waves of attacks on Kyiv since the beginning of May, a surge in strikes that the government says appears aimed at derailing Ukraine’s preparations for a major counter-offensive to try to end Russia’s invasion.

A child was one of two people injured by falling debris in a region outside the Ukrainian capital as air defences shot down what the air force said on Friday were 15 Russian cruise missiles and 21 drones.

“The occupiers are not stopping their attempts to terrorise the Ukrainian capital with strike drones and missiles,” it said.

Russian officials reported cross-border shelling from several areas of northern Ukraine on Friday in the latest sign that Kyiv is starting to push back beyond its borders after more than 15 months of an all-out Russian assault.

The governor of Russia’s Belgorod region said two people had been killed and two others injured when Ukrainian forces shelled a road in the town of Maslova Pristan near the Ukrainian border.

“Fragments of the shells hit passing cars. Two women were travelling in one of them. They died from their injuries on the spot,” governor Vyacheslav Gladkov said. Russia said on Thursday it had repelled a second attempted incursion into the Belgorod region in just over a week by what it casts as pro-Ukrainian militants. Ukraine denies involvement.

The Freedom of Russia Legion blamed Russia for the shelling on Telegram, while posting images of what it said was one of its tanks in the nearby Russian village of Novaya Tavolzhanka and soldiers taking cover behind a wall during a gunfight.

“Near Tavolzhanka, the enemy destroyed a Renault car with civilians, mistaking it for a car with our sabotage group. At least two civilians were killed, and this is a direct consequence of the lack of professionalism of Putin’s army,” the Legion said on the Telegram messaging app.

The group describes itself as Russians fighting President Putin’s government to create a Russia that would be part of the “free world”.