KYIV, Ukraine — Ukraine rushed reinforcements to its northeastern Kharkiv region on Friday to hold off a Russian attempt to breach local defenses, authorities said, signaling a tactical switch in the war by Moscow that Ukrainian officials had been expecting for weeks.
Kharkiv's regional governor, Oleh Syniehubov, said intense overnight shelling targeted Vovchansk, a city with a prewar population of about 20,000 that is less than 5 kilometers (3 miles) from the Russian border. The barrage, which used powerful guided aerial bombs, artillery, rockets, tanks and mortars, killed at least one civilian and wounded five others, prompting authorities to begin evacuating about 3,000 people.
Then, around dawn, Russian infantry tried to penetrate Ukrainian defenses near Vovchansk, the Ukrainian Defense Ministry said, adding that it had deployed reserve units to fend off the attack.
Russian military bloggers said the assault could mark the start of a Russian attempt to carve out a ''buffer zone'' that President Vladimir Putin vowed to create earlier this year to halt frequent Ukrainian attacks on Belgorod and other Russian border regions.
By mid-afternoon, Ukrainian troops were still holding firm against the assault, Syniehubov said.
''Active combat is ongoing in the settlements located 1-2 kilometers (miles) away from border with Russia,'' he told Ukrainian television.
Ukraine previously said it was aware that Russia was assembling thousands of troops along the northeastern border, close to the Kharkiv and Sumy regions. Although Russia's most recent ground offensive had been focused on parts of eastern Ukraine farther south, Ukrainian intelligence officials said they had expected an attack in the northeast, too. The Kremlin's forces stepped up their bombardment of Kharkiv, Ukraine's second-largest city, in late March.
President Volodymyr Zelenskyy said Ukraine's military had anticipated this latest attack and had calibrated its response.
