The photo with Ukrainian soldiers holding the flag near the entry sign to Kupiansk suggests they have already reached the outskirts of the city.
Kupiansk is the major logistics hub for the Russian Izium grouping of forces located to the south of Kupiansk and Balakliia. The sign is located more than 50 kilometers behind the Sep 6 frontline at the beginning of the Ukrainian offensive in Kharkiv Oblast. If Ukrainian forces take control over Kupiansk the main Russian supply line to Izium would be cut.
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