Russian forces continued their advance across northeastern Ukraine on Sunday, seizing a number of small settlements along the border and forcing Ukrainian troops to retreat from some positions, according to the Russian and Ukrainian militaries, as well as aid workers.
Russia’s Defense Ministry said on Sunday that its troops had captured four more settlements — all but one located directly north of Kharkiv, Ukraine’s second largest city — as they pressed ahead with a new offensive launched on Friday. Aid workers confirmed that Russian troops had advanced deeper inside Ukrainian territory and were now threatening several small towns on the outskirts of Kharkiv.
A Ukrainian military unit fighting in the area said the Russian forces were pushing hard from the Russia-Ukraine border toward Kharkiv.
“Today, during heavy fighting, our defenders were forced to withdraw from a few more of their positions, and today, another settlement has come completely under Russian control,” said a video statement released on Saturday night by Hostri Kartuzy, a Ukrainian special forces unit. “The Russians are dying in droves. But they are pressing on regardless and succeeding in some areas.”
Gen. Oleksandr Syrsky, Ukraine’s top military commander, said that the situation in the Kharkiv region had “significantly worsened” this past week, but that Russian attempts to break through Ukrainian defensive lines had been unsuccessful so far.
Ukraine’s outnumbered and outgunned troops were already stretched thin trying to defend a 600-mile front running from south of Kharkiv to the city of Kherson on the Black Sea. By opening a new front north of Kharkiv, the Russian army aims to further stretch the Ukrainian lines and make it easier to break through at certain points, military experts say.
“The Russians have understood, just as a lot of analysts have, that the major disadvantage that Ukraine is currently suffering from is manpower,” said Franz-Stefan Gady, a Vienna-based military analyst. “By thinning out the front line, you are increasing the odds of a breakthrough.”
Mr. Gady and other experts said the immediate objective of the new Russian offensive was to force the Ukrainian army to draw away troops that are critically needed south of Kharkiv, particularly around the embattled town of Chasiv Yar, a Ukrainian stronghold in the southeastern Donetsk region.
Russian forces have been assaulting Chasiv Yar for several weeks. The capture of the stronghold would put several towns critical to Ukrainian military logistics on the eastern front directly in Moscow’s line of fire.
With fighting raging in the area, cross-border fire has intensified and Russia accused Ukraine on Sunday of hitting a multistory building in the Russian city of Belgorod, about 45 miles from Kharkiv. Vyacheslav Gladkov, the governor of the Belgorod region, said that 19 people had been injured in the shelling of the city, and that no deaths had been reported yet.
Russia’s Defense Ministry said fragments from an intercepted Ukrainian missile had struck the building. Mr. Gladkov posted a video from the scene showing an enormous hole in a building. “The entire entrance from the tenth to the first floor collapsed,” he said.
The claims could not be independently verified. Andriy Kovalenko, a Ukrainian official working on Russian disinformation, said the claims were “untrue” and intended as a provocation to “justify further attacks on residential buildings in Ukrainian cities.”
Russian forces launched a complex, surprise offensive on Friday, deploying fighter jets, artillery units, infantry and armor, surging across the northeastern frontier between Russia and Ukraine.
Russian troops quickly seized dozens of square miles of Ukrainian territory. Civilians living in the small towns and country villages along the border have been caught in the crossfire, and many are desperately trying to escape. More than 4,000 people have been evacuated, Kharkiv’s governor said on Sunday morning. Some of them were extracted with their pets. Others have been taken out on stretchers.
All day Saturday, small vans and even bright yellow school buses rumbled over deeply cratered roads littered with bomb shrapnel to rescue people who were trapped in towns that had come under intense shelling.
On Sunday, people who had evacuated were pleading with their loved ones still in the border villages to leave. Svitlana Nahorna said her husband was trapped in Bilyi Kolodiaz, a small village northeast of Kharkiv.
“I’ve been pleading with him to leave, but he refused,” she said while in a shelter for displaced people in Kharkiv. “We’re afraid whether it’s even possible to get him out now.”
In addition to trying to distract the thinly stretched Ukrainian forces from the contested battlefields of eastern Ukraine, military analysts believe that the Russians are also trying to carve out a buffer zone along the border to make it more difficult for Ukrainian forces to launch artillery into Russia. The Russians might also be trying to get close enough to Kharkiv to shell it and sow panic, as they did in the early days of the war in 2022, analysts say.
Mykola Bielieskov, a military analyst at the government-run National Institute for Strategic Studies in Ukraine, said a buffer zone of 10 to 15 kilometers deep into Ukrainian territory “for sure would create problem for Kharkiv by putting the city within the range of” Russia’s artillery.
It remains unclear whether Russia will succeed in its goal of drawing away enough Ukrainian troops from other sections of the front. Ukrainian officials said they had sent reinforcements to the Kharkiv region, without specifying how many units.
Mr. Bielieskov said Russia had not yet committed enough troops to the Kharkiv offensive “to create real dilemmas for Ukraine’s military command and force a major redeployment from other parts of the front.”
Still, President Volodymyr Zelensky of Ukraine seemed to hit a note of increasing concern in an address on Saturday. Citing all of the combat engagements in eastern Ukraine, he added, “It’s extremely difficult.”
In a similar tone, the British foreign secretary, David Cameron, warned on British television on Sunday that the situation around Kharkiv was “extremely dangerous.”
Oleksandra Mykolyshyn contributed reporting from Kharkiv.