A Ukrainian counteroffensive that already has reclaimed thousands of miles is breaking through Russian lines in the Kherson region recently annexed by Moscow, Kremlin-installed officials said Monday.

Vladimir Saldo, the Russian-installed head of Ukraine's Kherson region, said on state television that multiple settlements about 70 miles northeast of the city of Kherson on the bank of the Dnieper River had been overrun.

"It's tense, let's put it that way," Saldo said in a translation by Reuters....