Among the dead is a 12-year-old girl, police said Sunday. The attack came as Russian forces continue to advance in northeastern Ukraine after crossing the border earlier this month and opening a new front in the two-year-old conflict.
Kharkiv has seen a spate of Russian attacks, as Russia seeks to tie up Ukrainian forces elsewhere and create a buffer zone.
Ukrainian President Volodymyr Zelensky called the strike a "brutal attack" in a post on X, later writing that "Russia is run by men who want to make it a norm - burning lives, destroying cities and villages, dividing people, and erasing national borders through war."
Officials have said there were nearly 200 people inside the building when the strike occurred.
According to Chief of the Investigative Department of the Kharkiv Regional Police Serhii Bolvinov, investigators and forensic experts spent the night searching the ruins of the store for human remains.
"We fear that they will have to sift through the ashes to find the remains and identify the victims," he continued.
Ukraine's Interior Minister, Ihor Klymenko, said Sunday that the hours following the strike were "hellish" and thanked everyone who helped to put out the flames that engulfed the hardware store after the attack.
Oleh Syniehubov, head of the Kharkiv regional military administration, noted that there is "not a single military object nearby" the site of the strike.
He said the remains of 10 people who died in the strike had been identified and eight people were still missing.
Meanwhile, further south in the Kherson region, authorities warned residents to avoid open spaces as there have been reports of explosions.
"The enemy is attacking from the temporarily occupied left bank," Roman Mrochko, the head of the Kherson City Military Administration, said in a Telegram post Sunday. "Do not stay in open areas. Take care of yourself and your loved ones," he wrote.
Russian forces attacked Ukrainian frontline positions in Kharkiv 15 times over the weekend, General Serhii "Marcel" Melnyk, Commander of the Kharkiv city defense forces, said earlier on Sunday, adding that "some of the attacks are still ongoing."
Overnight Saturday into Sunday, Russian forces launched 14 missiles and over 30 unmanned aerial vehicles (UAVs) at Ukraine, according to the Ukrainian military.
Seven people were killed in Russian strikes on the city Thursday, after locations including a printing house were targeted.
"Russia continues its savage attacks on Kharkiv this week, striking a busy shopping center, a book publishing house and other civilian targets," US Ambassador to Ukraine Bridget Brink said Saturday. "We condemn these attacks and commit to holding Russia accountable for its unprovoked war," she added.
After Saturday's attack, Zelensky reiterated that "if Ukraine had enough air defense systems and modern combat aircraft, such Russian strikes would have been impossible."
"That is why we are appealing to all leaders, to all states: we need a significant strengthening of air defense," he said.
Zelensky has since appealed to US President Joe Biden and Chinese leader Xi Jinping to attend a peace summit in Switzerland next month.
"Please, show your leadership in advancing the peace - the real peace and not just a pause between the strikes," Zelensky said. "The efforts of the global majority are the best guarantee that all commitments will be fulfilled," he added.
Meanwhile, at least two people were killed and at least 10 injured as a result of a Ukrainian strike on a Russian village in the Belgorod region, the region's governor Vyacheslav Gladkov said Saturday.
Among the injured is an 8-year-old boy, he said, adding that "all victims had shrapnel wounds in various parts of the body."
As a result of the strike, a private residential building caught fire, and about 20 other buildings and 23 cars sustained damage. "All operational services are working on site," Gladkov said.
This story has been updated with new information. Darya Tarasova contributed reporting.
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