A Russian strike killed at least 17 people at a market in east Ukraine Wednesday, officials said, in an attack that President Volodymyr Zelensky described as deliberate and "heinous".
The attack came hours after US Secretary of State Antony Blinken made an unexpected trip to Kyiv, where he vowed Washington would stand "side by side" with Ukraine as it pressed ahead with its counteroffensive against Russia.
Projectiles tore through the centre of Kostiantynivka -- a town of nearly 70,000 people in the Donetsk region -- in one of the deadliest strikes in weeks.
"They smashed everything, all the shop windows, everything was strewn around," an eyewitness told AFP.
"Thank God we are alive, of course. But the girls who were selling there, they are all dead," the witness said.
Rescue workers picked through the debris and carried some of the wounded for treatment past charred vehicles and kiosks torn to pieces in the blast, according to images distributed by officials.
"Seventeen people were killed and 32 injured as a result of the Russian shelling," Interior Minister Igor Klymenko said, announcing the rescue operation had ended.
Prime Minister Denys Shmygal said a child was among those killed in the attack, which took place about 20 kilometres (12 miles) from the front line.
"Anyone in the world who is still dealing with anything Russian simply ignores this reality," said Zelensky.
"Heinous evil. Brazen wickedness. Utter inhumanity."
He later accused Russia of deliberately targeting civilians and said there were no military units "anywhere near" the scene.
- 'Good progress' -
During a meeting with Zelensky, Blinken reiterated Washington's support for Kyiv in its fight to liberate territory in the south and east.
"We are determined in the United States to continue to walk side by side with you. And President Biden asked me to come to reaffirm strongly our support, to ensure that we are maximising the efforts that we're making," he told Zelensky.
"We see the important progress that's being made now in the counteroffensive and that's very, very encouraging," he added.
Blinken is expected to announce "more than a billion dollars in new US funding for Ukraine", said a senior State Department official.
The Kremlin dismissed Blinken's Kyiv visit, arguing US aid would not "influence the course of the special military operation" -- Moscow's term for its offensive.
Kremlin spokesman Dmitry Peskov accused Washington of wanting to "keep Ukraine in a state of war, to wage this war till the last Ukrainian".
Kyiv's army meanwhile said it was pressing on with "offensive operations" towards eastern Ukraine's war-battered town of Bakhmut, which fell to Russian forces in May, and the southern Moscow-occupied city of Melitopol.
The US has supplied key weaponry to Ukraine that allowed it to launch its counteroffensive this summer and Blinken told Kuleba that "we've seen some good progress".
But Ukraine has in recent weeks become increasingly frustrated with criticism that the counteroffensive has been too slow.
Russia said Wednesday it had "improved its tactical position" near the northwestern city of Kupiansk, where it has led a local offensive for weeks.
It also hit Ukraine's south-western Odesa region, near the border with Romania, with drone attacks overnight, killing one person.
- 'Everything possible and impossible' -
In what was hailed as a historic move, Ukrainian lawmakers approved the nomination of Crimean Tatar Rustem Umerov as Kyiv's new wartime defence minister Wednesday.
Crimean Tatars are an ethnic minority hailing from the Black Sea peninsula, which was annexed by Russia in 2014.
"I will do everything possible and impossible for the victory of Ukraine -- when we liberate every centimetre of our country and every one of our people," he said in a post on social media.
The 41-year-old businessman has been involved in prisoner exchange negotiations involving Saudi Arabia and grain export talks with Turkey and the United Nations.
"Children, prisoners of war, political prisoners, civilians... are waiting for us," he said.
Zelensky had nominated Umerov as new defence minister after the resignation of Oleksiy Reznikov, calling for "new approaches" in the wake of several corruption scandals in the ministry.
"It is the highest state post ever held by a Tatar (from Crimea)," Sergiy Leshchenko, an advisor to the presidential administration, told AFP.
- Danish PM visits -
A string of Western leaders has visited Kyiv since Moscow launched its invasion in February 2022, pledging support in the battle against Russian forces.
Denmark's Prime Minister Mette Frederiksen was the latest to travel to the Ukrainian capital Wednesday, after pledging to supply Ukraine with 19 F-16 fighter jets.
Denmark and the Netherlands last month announced they would provide the advanced jets to strengthen Kyiv's Soviet-era air force.
State Department spokesman Matthew Millar said Blinken had met Frederiksen as they travelled to Ukraine and thanked her for the "decision to donate F-16 jets to Ukraine."