Ukrainian Defences Face Challenge as Russian Troops Make Gain

Days before the leaders of Russia and the US hold a summit meeting in Alaska, Moscow's forces breached Ukrainian lines in a series of infiltrations in the country's industrial heartland of Donetsk.

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DONETSK REGION:

This week's advances amount to only a limited success for Russia, analysts say, since it still needs to consolidate its gains before achieving a true breakthrough. Still, it's a potentially dangerous moment for Ukraine.