The Russian army is intensifying its attacks in eastern Ukraine, military authorities said Tuesday, even as the Kremlin's forces try to check a stunning weeklong incursion into Russia by Kyiv's troops.

Ukraine's General Staff said Tuesday that over the previous 24 hours Russian troops launched 52 assaults in the area of Pokrovsk, a town in Ukraine's Donetsk region that is close to the front line. That's roughly double the number of daily attacks there a week ago.