Russian drones have struck the Black Sea city of Mykolaiv, setting a hotel on fire and damaging energy infrastructure, the local Ukrainian governor has said.

Vitaliy Kim said Russian drones “seriously damaged” the hotel and affected heat-generating infrastructure in the city. He added that there were no casualties.

Russian state agency RIA carried claims that the strike on Mykolaiv targeted a shipyard where naval drones are assembled, as well as a hotel housing “English-speaking mercenaries” who have fought for Kyiv.

The RIA report cited Sergei Lebedev, described as a co-ordinator of local pro-Moscow guerrillas. His claim could not be independently verified.

Also on Sunday morning, the Russian defence ministry said 17 Ukrainian drones were downed overnight over four regions in the country’s south-west. Three drones were intercepted near an oil depot in Lyudinovo. There were no immediate reports of any casualties or damage.

One of the drones damaged communications infrastructure in Russia’s Belgorod province, which borders Ukraine, governor Vyachaslav Gladkov said. There were no immediate reports of casualties.

The Russian Defence Ministry, meanwhile, claimed its forces had destroyed ammunition depots and military equipment housed at three airports across Ukraine, including assault drones stored at Kamyanka Airfield in the country’s east. The ministry’s online update on Sunday said the attacks took place over the last 24 hours. There was no immediate comment from Kyiv.

Russian shelling on Saturday and overnight wounded at least seven civilians across Ukraine, according to Ukrainian officials.

The Donetsk and Kharkiv regions have seen fierce clashes in recent weeks as Russian forces seek to grind out gains along the 620-mile front line, while ammunition shortages have increasingly hamstrung Ukraine’s defences.

Russian troops “will likely make significant gains in the coming weeks” while Kyiv awaits much-needed arms from a huge US aid package to reach the front, a Washington-based think tank said.

In its latest operational assessment, the Institute for the Study of War said Moscow’s forces have opportunities to push forward around Avdiivka, the eastern city they took in late February after a gruelling, months-long fight, and threaten nearby Chasiv Yar.

Its capture would give Russia control of a hilltop from which it can attack other key cities forming the backbone of Ukraine’s eastern defences.

Despite this, the institute assessed that neither of these efforts by Moscow are likely to cause Kyiv’s defensive lines to collapse.