Battle of Kostiantynivka

After the Russian capture of Toretsk in August 2025, its troops continued launching assaults to the northwest in the direction of Kostiantynivka.^[8] By 23 August, Russian forces captured the village of Kleban-Byk [uk], located in between the cities of Toretsk and Kostiantynivka.^[9]

The first Russian infiltration attempts into Kostiantynivka occurred at the end of October 2025.^[10] Russian assault groups began entering the city from the southeast.^[11] The Ukrainian 28th Mechanized Brigade managed to thwart one of these attempts.^[12] An estimated 4,800 residents remained in the city by early November.^[13][14] On 21 November, Russian forces seized the village of Ivanopillia located to the south of Kostiantynivka.^[15][16] Furthermore, its troops were able to advance in the southeastern parts of the city.^[17][18]

In early December, the Russian army made further advances into southeastern Kostiantynivka along Mahistralna Street.^[19] Meanwhile, the remaining residents struggled to survive in their damaged homes.^[20] The Ukrainian Ministry of Internal Affairs released footage which showed the destruction of the city.^[21] At the same time, Russian units reached Kustanaiska Street in southeastern Kostiantynivka.^[22] Russian chief of the General Staff, Valery Gerasimov, claimed on 18 December that Russia controls 50 percent of Kostiantynivka.^[23] While the Institute for the Study of War (ISW) estimated that Russia controls about 5 percent of the city.^[24][25] At the end of December, Russian forces captured a trench system in eastern Kostiantynivka, thus reaching the T-0504 Bakhmut – Pokrovsk highway.^[26] Moreover, its troops started advancing along Ostrovskoho Street towards the railway station.^[27] Further south, Ukrainian forces repelled Russian attacks from Ivanopillia in the direction of southern Kostiantynivka.^[5]

At the beginning of 2026, Russian forces began launching assaults from Yablunivka to southwestern Kostiantynivka, through the H-20 Donetsk – Kramatorsk highway.^[2] Soldiers of the Ukrainian 24th Mechanized Brigade installed anti-drone nets above several roads around the city to protect their resupply.^[28] Analysts noted that the seizure of Kostiantynivka is part of Russia’s 2026 war priority.^[29] Russian units infiltrated toward the village of Illinivka located to the west of Kostiantynivka by 17 January.^[30] In addition, its forces attempted to gain a foothold in the most western districts of the city.^[31] South of Kostiantynivka, Russian forces claimed to have captured Berestok.^[32][33] In the subsequent weeks, the Russian army intensified their efforts to strike Ukrainian logistics towards the city.^[34][35] The ISW assessed on 16 February that Ukrainian forces no longer maintain positions to the south of Berestok.^[36] This resulted in full Russian control over the Kleban-Byk Reservoir.^[37] Russian forces struck the dam near the settlement of Osykove causing flooding in the area. This made the road connecting Oleksiievo-Druzhkivka and Kostiantynivka impassible, further complicating Ukrainian logistics towards the city.^[38][39]

Meanwhile in downtown Kostiantynivka, Ukrainian troops captured a Russian soldier near the railway station, indicating Ukrainian control over the central station.^[40] Ukrainian forces successfully repelled Russian assaults on the city throughout March 2026.^[41][42][43] Geolocations of video footage shows that Russian and Ukrainian positions inside Kostiantynivka are interspersed, making the exact frontline hard to determine.^[44] Russian units managed to reach the zinc plant in central Kostiantynivka following an infiltration operation.^[45][46] An estimated 2,500 residents still lived in the city by April 2026.^[47]