KRAMATORSK, Ukraine — Ukraine continued its show of defiance against Moscow’s illegal annexation claims on Sunday, with soldiers and police officers fanning out to search for Russian stragglers in a key city reclaimed by Kyiv’s forces even as President Vladimir V. Putin declared it part of Russia.
President Volodymyr Zelensky of Ukraine said that Lyman, a strategic railway hub in the Donetsk region, had been fully cleared by Sunday afternoon, as Ukrainian forces conducted patrols and delivered aid to residents who had survived months of Russian occupation and weeks of battle as Ukraine fought to retake it. The city now lies largely in ruins, without electricity, water or regular food supplies, according to Stanislav Zagrusky, the Ukrainian police chief responsible for the area.
Still, Mr. Zagrusky said in an interview, the resumption of Ukrainian police patrols late on Saturday — hours after the Ukrainian Army declared the city liberated and Russia’s military conceded that it had retreated — underlined the absurdity of the Kremlin’s grandiose ceremony a day earlier announcing that the territory had been incorporated into Russia.
“We absolutely don’t care what they say, what decrees they issue, what announcements they make,” he said of the Kremlin authorities, deploring the conditions in which Russian troops had left residents of Lyman during the occupation: “They did absolutely nothing for the people all this time.”
“They didn’t try to restore electricity, or water and people lived without regular food supplies,” he went on, adding that many residents needed medical care.
It was unclear how many people remained in the city, which had a prewar population of 20,000. Artillery strikes damaged much of Lyman.
Ukrainian commanders had initially thought that they would retake Lyman quickly, but Russia’s military sent reinforcements. Fierce fighting ensued in dense forests and along the banks of the Siversky Donets River as Ukraine cut off the roads used to move troops and ammunition into the city. Ukrainian forces nearly completed an encirclement of Lyman, even as Mr. Putin claimed the region around the city as part of Russia on Friday.
“In Lyman and around it, there were significantly strong forces,” Col. Sergei Cherevaty, a spokesman for Ukrainian troops fighting in the east, said in an interview.
Russian soldiers retreated chaotically, breaking from their units and escaping in smaller groups into the surrounding forests, Colonel Cherevaty said, and many were killed or captured. About 2,000 to 3,000 Russian soldiers remained in Lyman by the time Ukrainian forces arrived at the outskirts of the city on Friday, he said. It was unclear on Sunday how many Russian soldiers had fallen into Ukrainian hands.
In an article published on Sunday in a major Russian newspaper, Komsomolskaya Pravda, a prominent war correspondent traveling with fleeing Russian forces described demoralized troops with “empty eyes” who barely escaped Lyman with their lives.
In an unusually candid assessment, the account, written by Aleksandr Kots, said that in the last few days of their occupation, Russian forces in Lyman were plagued by desertion, poor planning and the late arrival of reserves.
“The risk of encirclement or shameful imprisonment became too great, and the Russian command made a decision to fall back,” he wrote.
There was no public comment from Mr. Putin’s office about the loss of Lyman, even as pro-war commentators and two of his closest allies sharply criticized the Defense Ministry for retreating from the city. Seemingly unfazed by its military setbacks, Moscow continued to press ahead with its sham annexation effort on Sunday, as the country’s rubber-stamp Constitutional Court formally accepted Mr. Putin’s decision to claim four Ukrainian regions as part of Russia.
Mr. Zagrusky, the police chief of the Kramatorsk district, which includes Lyman, said that while the Ukrainian military took prisoners after the battle, police officers had made no arrests of Russian stragglers as of midday on Sunday. His officers found that Russians had hastily abandoned a police station, leaving it littered with garbage.
The Ukrainian military posted a taunting message on Twitter asserting that it had captured prisoners and mocking the Russian explanation of the withdrawal as a redeployment to the east.
“We thank the ‘Ministry of Defense’ of Russia for successful cooperation,” the Ukrainian tweet said. “Almost all Russian troops deployed to Lyman were successfully redeployed either into body bags or into Ukrainian captivity.”