Ukraine's interior minister and a child were among at least 14 people killed on Wednesday when a helicopter crashed into a nursery and set it ablaze in a suburb of the capital Kyiv.
Separately, Ukraine reported more fighting along front lines hundreds of kilometers (miles) away in the east, where both sides have taken huge losses for scant gain in intense trench warfare over the past two months.
Ukrainian officials said it was too early to determine what caused the helicopter crash. None immediately spoke of any attack by Russia, which invaded Ukraine last February and has been battering Ukrainian cities far from front lines with missiles and drones almost daily since October.
Dozens of people were injured including children, many suffering burns, after the French-made Super Puma helicopter went down in the fog in Brovary on the eastern outskirts of Kyiv, plummeting into the nursery grounds.
Ukrainian state emergency services said 14 people in total had been killed. Government agencies had earlier published higher death tolls ranging up to 18.
Interior Minister Denys Monastyrskyi, who was on board the helicopter, was among the dead. He was the most senior Ukrainian official to die since the war began with a Russian invasion in February last year.
Residents described a frantic rescue.
"We saw wounded people, we saw children. There was a lot of fog here, everything was strewn all around. We could hear screams, we ran towards them," Hlib, a 17-year-old local resident, told Reuters. "We took the children and passed them over the fence, away from the nursery as it was on fire."
The entire side of the nursery building was charred, with a gaping hole above the entrance, where the helicopter's rotor blades rested. Nearby, debris was strewn over a muddy playground and the helicopter wreckage lay crumpled by an apartment block.
Several dead men lay in a courtyard, wearing blue uniforms and black boots visible from under foil blankets draped over the bodies.
Vitaliy, 56, said he saw the aircraft fall quickly and crash onto the grounds of the nursery before debris was hurled further into the block of flats. "I thought it was the engine from a rocket or something like that, something very large," he said.
President Volodymyr Zelenskiy ordered an investigation into what he said was a "terrible tragedy".
"The pain is unspeakable," he said in a statement.
Later, in a question and answer session by video link with the World Economic Forum (WEF) in Davos, Switzerland, Zelenskiy said he was not worried about his own personal security in the wake of the helicopter crash.
Monastyrskyi died alongside his first deputy, Yevheniy Yenin, and other ministry officials flying in the helicopter operated by the state emergency service.
Ukraine's SBU State Security Service said it would consider possible causes including a breach of flight rules, a technical malfunction or intentional destruction.
Zelenskiy: Give us western tanks faster
Since Ukraine wrested back significant territory in the east and south in the second half of 2022, front lines have hardened and Kyiv says new Western weapons especially heavy battle tanks are vital for it to regain momentum this year.
In a speech by videolink to the WEF, Zelenskiy said Western supplies of tanks, and air defense systems to blunt Russia's missile strike campaign, should come more quickly and be delivered faster than Moscow is able to carry out attacks.
In the latest announcement of new aid, Canadian Defense Minister Anita Anand visited Kyiv on Wednesday and pledged 200 Senator armored personnel carriers.
On Friday, Western allies will gather at a US air base in Germany to offer more weapons for Ukraine. Attention is focused in particular on Germany, which has veto power over any decision to send its Leopard tanks, fielded by NATO-allied armies across Europe and widely seen as the most suitable for Ukraine.
Polish President Andrzej Duda told the Davos gathering he was afraid Russia was preparing a new offensive in Ukraine within months and it was therefore crucial to provide additional support to Kyiv with modern tanks and missiles.
Poland and Finland have already said they will send Leopards if Germany approves them. Berlin says a decision will be the first item on the agenda of Boris Pistorius, named Germany's new defense minister earlier this week.
Lithuanian Foreign Minister Gabrielius Landsbergis said in Davos that he expected a decision to send tanks. "I'm confident because this is what I'm hearing here, talking with other leaders. There is momentum," Landsbergis told Reuters.
Russian President Vladimir Putin, visiting an air defense factory in St Petersburg, said Russia's military industrial might meant "victory is assured, I have no doubt about it".
Foreign Minister Sergei Lavrov said Moscow saw no prospects of peace talks and there could be no negotiations with Zelenskiy. Russia has said talks are possible only if Ukraine recognizes Moscow's claims to Ukrainian territory; Kyiv says it will fight until Russia quits all of Ukraine.
In the central city of Dnipro, the civilian death toll from a missile that struck an apartment block on Saturday rose to 45, including six children, among them an 11-month-old boy, Zelenskiy said in his nightly video address on Tuesday.
Around 20 other people are still missing after the attack, the deadliest for civilians of a three-month-old Russian missile bombardment campaign against cities far from the front.
Moscow denies intentionally targeting civilians. It launched what it calls its special military operation in Ukraine last year saying Kyiv's increasing ties with the West posed a security threat.
Tens of thousands of people have been killed and millions forced to flee homes in what Kyiv and the West call an unprovoked invasion to subdue Ukraine and seize its land.
