On Sunday, at least two civilians were killed and four others injured in a series of Ukrainian drone strikes across Russia’s Belgorod Region, regional governor Vyacheslav Gladkov said.

A drone strike targeted a vehicle carrying a married couple and their son in the village of Nechyaevka, leaving the father and son dead at the scene while the mother was hospitalized. In Gubkin city, another attack on a commercial building injured a young man and a teenage girl who were sitting in a car parked outside; the girl suffered a brain injury and remains in critical condition. A separate incident in Belgorod city left another woman wounded.

Governor Gladkov reported that nearly a dozen residential buildings were damaged by the strikes. Ukraine has launched over 600 drones deep inside Russia between Friday and Saturday, escalating attacks to Sunday. On Monday, a kamikaze drone hit a residential skyscraper in Moscow near the capital’s business district.

Russia has accused Ukraine of deliberately targeting civilians with Western-supplied weapons. Last month, the Russian Defense Ministry published what it described as a list of European companies involved in manufacturing drones for Ukraine and warned Kiev’s backers that further escalation could occur.