The rocket attack at Kramatorsk comes as Russia steps up its offensive in the east, and Ukrainian authorities have been trying hard to evacuate civilians.
The rocket attack that struck a railway station at Kramatorsk in eastern Ukraine killed at least "50 people including five children" and wounded "over 100", according to Ukrainian authorities.
There was swift condemnation from the Kyiv government and European politicians, none of whom were in any doubt as to who was to blame as they condemned Russia for targeting civilians.
The station has been heavily used by evacuees, and officials say thousands of people were there at the time of the attack.
Late on Friday morning, Ukraine's state railway company said two rockets struck the station through which many Ukrainians had passed in recent days, fleeing the conflict zone in the Donbas region.
"Two rockets hit Kramatorsk railway station," Ukrainian Railways said in a statement, adding that according to "operational data... more than 30 people were killed and more than 100 were wounded".
Local authorities in Ukraine said later that at least 50 had died, including five children.
Ukraine condemns 'deliberate slaughter' by Russia
The head of Ukraine's railways, Olexander Kamyshin, said on the messaging app Telegram that it was a "deliberate strike".
Ukrainian President Volodymyr Zelenskyy denounced an "evil that knows no bounds" unleashed by Russia.
"Without the strength and the courage to face us on the battlefield, they (the Russians) are cynically destroying the civilian population. It is an evil that knows no bounds. And if it is not punished, it will never stop,” Zelenskyy wrote on Telegram, denouncing the “inhumane” methods of the Russian forces.
Ukraine's foreign minister was if anything even more forthright. "Russians knew that the train station in Kramatorsk was full of civilians waiting to be evacuated," Dmytro Kuleba tweeted.
"Yet they stroke it with a ballistic missile, killing at least 30 and injuring at least a hundred people. This was a deliberate slaughter. We will bring each war criminal to justice."
The EU's foreign policy chief Josep Borrell, in Kyiv with Commission president Ursula von der Leyen, took to Twitter to blame Russia for what he called the "indiscriminate attack".
"This is yet another attempt to close escape routes for those fleeing this unjustified war and cause human suffering," he said.
Russia denies responsibility
The defence ministry in Moscow denied that Russia was involved in "an alleged missile attack on the railway station in Kramatorsk".
A statement posted on Facebook said Kyiv's claims were "a provocation and are absolutely untrue".
It said there were no Russian "firing missions" in the area and said the wreckage was of a Tochka-U missile "used by Ukrainian Armed Forces only".
The Russian statement is in line with a consistent policy of blanket denial that long precedes its war against Ukraine.
Kramatorsk attack comes amid mass evacuations
The rocket attack at Kramatorsk comes as Russia steps up its offensive in eastern Ukraine, having withdrawn its troops from the Kyiv region and the north.
Moscow has made the conquest of the Donbas region -- which has been partly controlled by pro-Russian separatists since 2014 -- its priority objective.
Pavlo Kirilenko, the governor of the Donetsk region, said thousands of people had been at the station at the time the rockets struck. The office of Ukraine’s prosecutor-general said about 4,000 civilians were in and around the station, most of them women and children.
Russian-backed separatists control part of the Donetsk region, but Kramatorsk is known as the "capital" of the area that remains under Ukrainian government control.
Ukrainian authorities have been trying hard to evacuate civilians as Russian forces multiply attacks in the south and east. At least twice this week civilians have been urged to "leave while they can".
Evacuations by train, which had been interrupted due to damage to part of the railway, had resumed overnight from Thursday to Friday, said the governor of the Luhansk region, Sergiy Hardai. For several days he had been encouraging people not to "condemn themselves to death" by staying.
"Three evacuation trains carrying residents of the Luhansk and Donetsk region were able to leave for the west. The track has been repaired," he said early Friday, before the attack on Kramastorsk station.
Photos taken two days ago showed platforms at the station crammed with passengers awaiting trains to other parts of the country.
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