Russian forces have made fresh tactical advances into Kostiantynivka, the Institute for the Study of War (ISW) assessed on 10 June. The city sits at the southern tip of Ukraine's Donetsk Oblast Fortress Belt — Moscow's main effort for the spring-summer 2026 offensive. Russia missed its own May deadline to take the city, and the wider fortified chain stays out of operational reach.

Two Russian tactical groups push into eastern Kostiantynivka

Two named Russian formations have pushed into eastern Kostiantynivka from the south, Ukrainian military observer Kostiantyn Mashovets reported on 10 June. He identified them as the "Bakhmut" tactical group and the "Dzerzhinsk" (Toretsk) tactical group. The "Bakhmut" group is built around Russia's 3rd Army Corps (AC) under the Southern Grouping of Forces. The "Dzerzhinsk" group operates in the area of responsibility of the 8th Combined Arms Army (CAA) of the Southern Military District. It likely includes elements of five CAAs, the 3rd AC, and Russian naval fleets, Mashovets noted.

Elements of the "Bakhmut" group pushed from Stupochky through Novodmytrivka into northeastern Kostiantynivka. They also advanced along the T-0504 Pokrovsk-Bakhmut road as far as the city's railway station. The "Dzerzhinsk" group moved from Illinivka, south of the city, into areas stretching from northwestern to southwestern Kostiantynivka near the railway station. Mashovets assessed that it has likely achieved a tactical breakthrough in the western, central part of the city. Forward assault elements of the two groups now stand roughly two kilometers apart. Russian forces have so far failed to seize the railway station. Ukrainian troops cleared the village of Dovha Blaka southwest of the city of Russian infiltrators.

Eight months of grinding, one missed deadline

ISW noted that Russian forces opened the campaign for Kostiantynivka in August 2025 after seizing the majority of Chasiv Yar and Toretsk, with Toretsk alone running to roughly 26,000 Russian casualties. The first Russian troops infiltrated Kostiantynivka itself in October 2025. Russia has since worked into at least 12.69% of the city. Ukrainian officials reported earlier this spring that the Russian command had set a May 2026 deadline for the seizure. That deadline has come and gone.

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Russia has poured forces into the effort regardless. Ukrainian Commander-in-Chief Oleksandr Syrskyi said on 2 May that Russian activity in this direction noticeably increased in April. Russian units in the area had reportedly been replenished by 80% as of 6 June, ISW noted. The Russian command reportedly redeployed elements of the 70th Motorized Rifle Division to the Kostiantynivka-Chasiv Yar area last December. The redeployment likely came in preparation for the spring push.

Tactical gains likely, the Fortress Belt still out of reach

ISW assessed that Russian forces will likely keep infiltrating throughout Kostiantynivka. They will likely consolidate positions in parts of the city while suffering high casualties. Russia's 3rd AC northeast of the city appears to be struggling to dislodge Ukrainian forces from Chasiv Yar. That inhibits any move to envelop Kostiantynivka from the north. A Russian milblogger claimed on 9 June that Ukrainian forces recently counterattacked near Chasiv Yar. The milblogger added that Ukraine still holds Podilske and Mykolaivka west of the town.

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The northern flank of the Fortress Belt is also bogged down. Russia opened its spring-summer 2026 offensive with mechanized assaults around Lyman. Those assaults signaled intent to advance on Sloviansk from the northeast. They produced no significant gains, ISW noted. The Russian command likely shifted weight south to Kostiantynivka. Russia's Western Grouping of Forces covers the front from Kupiansk through Lyman. It likely lacks the combat power to push on Sloviansk while balancing operations toward Kupiansk and Borova. 

Russia's overnight drone and missile barrage on 9 June killed and wounded civilians in the Kharkiv Oblast cities of Chuhuiv and Kharkiv, regional officials reported. More strikes over the past 24 hours left several people dead and dozens wounded elsewhere in Ukraine. Ukraine's Air Force said air defense stopped most of the drones, though missiles and others still reached homes.

Chuhuiv and Kharkiv bear the brunt

A series of Russian missile strikes on Chuhuiv overnight on 9 June killed at least three people and wounded six, the city's mayor, Halyna Minaieva, reported. Fire crews stayed at the impact sites as emergency services worked, she wrote, and the strikes damaged about eight apartment buildings and more than ten detached houses.

In Kharkiv—the regional capital—Russian drone strikes set off fires, damaged at least 18 cars, and blew out windows and facades in residential high-rises, Kharkiv Oblast head Oleh Syniehubov reported.

He said 15 people were hurt, among them three children, including a one-year-old boy, and three women were hospitalized. 

Both cities sit dozens of kilometers from the Russian border and have been struck repeatedly through the war.

A barrage of two missiles and 166 drones

Russia launched two Kh-59/69 guided air missiles from Voronezh Oblast and 166 strike drones overnight, Ukraine's Air Force reported. The drones included Shahed types, some jet-powered, along with Gerbera, Italmas, "Banderol" loitering munitions, and "Parodiya" decoys, launched from Oryol, Kursk, Bryansk, Primorsko-Akhtarsk, and Millerovo in Russia, occupied Donetsk, and Hvardiiske in occupied Crimea.

By 08:00, air defense had downed or suppressed 146 of the drones. Two missiles and 17 drones struck 18 locations, and debris from intercepted drones fell at eight more. 

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Zaporizhzhia counts the damage from the day before

A Russian drone attack the previous day damaged 11 residential buildings across three districts of Zaporizhzhia, the city council reported. Six apartment blocks and five detached houses in the Khortytskyi, Zavodskyi, and Kosmichnyi districts lost windows, balconies, doors, and roofs to blast waves and debris. No one was hurt, and priority repairs were finished.

A nationwide wave

• Russian attacks over 8 June killed two people in Sumy Oblast and wounded 13 across 21 hromadas, the regional police reported. A 78-year-old woman died in the Konotop hromada and a 71-year-old man in Seredyna-Buda, with a two-year-old boy and an eight-year-old boy among the injured.
• In Donetsk Oblast, Russian forces killed two residents, in Bilozerske and Druzhkivka, and wounded 11 more, nine of them in Sloviansk, Oblast head Vadym Filashkin reported. Police recorded 1,309 attacks on the oblast's front line and residential areas, damaging 53 civilian sites. Hours later, Russia dropped three FAB-250 glide bombs on Sloviansk's outskirts, destroying one home and damaging more than 20.
• In Kherson Oblast, drone and artillery attacks killed one person and wounded 13, including a child, Oblast head Oleksandr Prokudin reported. 
• Drone strikes in Dnipropetrovsk Oblast wounded three people. 
• Russian forces also hit 12 villages in four border hromadas of Chernihiv Oblast, the local border detachment told Suspilne.
• The Russians also attacked communities in Mykolaiv Oblast with drones, where the administration reported no casualties.