Russians penetrate key fortress city: 'We lost the fortress city, our soldiers are cornered'

Russian forces have reportedly penetrated deep into Kostiantynivka, a strategically vital Ukrainian city in the Donetsk region, with some Ukrainian soldiers describing the situation as dire and the city as effectively lost. The city is considered one of four "fortress cities" Russia aims to capture to secure the remainder of Donetsk Oblast. Russian President Vladimir Putin has emphasized Kostiantynivka's importance for liberating the entire region.

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We have effectively already lost the city. When there are so many Russians there, you can't say we're really holding it. They're just pushing our guys into a corner.

Reports from the ground paint a complex and concerning picture. One Ukrainian soldier told the Ukrainian portal Hromadske that "we have effectively already lost" the city, with a significant Russian presence inside. "When there are so many Russians there, you can't say we're really holding it. They're just pushing our guys into a corner," the soldier stated. A local Ukrainian commander warned that Russian movements north of the city could lead to Ukrainian units being encircled within one to two months if reinforcements do not arrive or defensive strategies do not change.

However, not all assessments are pessimistic. Former Commander-in-Chief of the Ukrainian Armed Forces Oleksandr Syrskyi had previously claimed that approximately 145 Russian infiltrators were in the city and suffering heavy losses. A commander known by the call sign "Kurt" shared a more optimistic view with the portal Suspilne, reporting intense fighting but asserting that "we still control most of the city, and the enemy is mostly pushed to the edges." He noted that Russian attempts to encircle and cut off Ukrainian forces were ongoing but being resisted, highlighting the significant challenge posed by Russian KAB bombs, which are reportedly used in hundreds of daily attacks.

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The situation in Kostiantynivka is very bad. It's not a question of whether we will lose it – we have actually already lost it.

Recent assessments from the Institute for the Study of War (ISW) suggest a widening Russian infiltration in Kostiantynivka, expanding beyond earlier estimates of presence in only 37% of the city. This comes after a period where Russian territorial gains had significantly slowed, with daily advances dropping from an average of 16.6 square kilometers in early 2025 to about one square kilometer in June of the current year. July even saw Russian forces reportedly losing territory. Despite this slowdown, Moscow appears to be attempting a renewed offensive, with Ukrainian drone forces commander Robert Brovdi reporting a rise in Russian soldiers involved in offensive operations and corresponding increases in Russian casualties during July.

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Intense fighting and shooting are taking place throughout the city. But we still control most of the city, and the enemy is mostly pushed to the edges. They are trying to encircle and cut us off, but we are holding the defense there. We are constantly under KAB strikes. That's the only way Russians manage to gain positions, and that's a big problem for us.