Russian forces close in on city that unlocks eastern Ukraine

If the city of Kostyantynivka falls, Russian troops could advance toward Ukraine's last remaining strongholds in the eastern Donbas region. The build-up of Russian forces near the city signals a major push to seize control of the area, which has been a key battleground in the ongoing war. Military analysts say losing Kostyantynivka would leave Ukrainian defenses in the east severely weakened.