Record numbers of refugees headed into Poland from Ukraine with the total number expected to surpass 1.0 million people later on Sunday as Russian forces escalated their invasion.
Fresh data shows Polish border guards cleared as many as 129,000 people at border crossings on Saturday, the most in a single day since the war started, bringing the total to 922,400, reports Reuters.
"Check-in is as simplified as possible," Polish Border Guard spokeswoman Anna Michalska said. "The point is to confirm the identity of persons, verify documents, check the databases if they are not wanted persons. It takes a few minutes."
"Forecasts indicate that today the number of people who entered Poland from Ukraine from February 24 will exceed one million."
At the Medyka crossing, the busiest along Poland's roughly 500-kilometre (310-mile) border with Ukraine, refugees streamed past boxes of clothes laid out along a path from the border crossing while Scouts handed out hot tea, food and toiletries.
Some carried babies, others dogs and cats wrapped in blankets. Many joined a queue for buses to the nearby town Przemysl where friends, relatives and volunteers waited to take them to other cities in Poland and beyond.
"In Kyiv there are many bombs and you sit in the basement and still hear it and because of that I left this city," said Anna Klimova, 21, who was travelling to Wroclaw to stay with her brother. "It's a really hard situation."
Poland's Ukrainian community of around 1.5 million is the region's largest and makes the country a major destination point for refugees, though fleeing Ukrainians also cross to safety through Slovakia, Hungary and northern Romania.
The number of refugees fleeing Ukraine surpassed 1.5 million on Sunday according to the head of the UN refugee agency, as Kyiv pressed the West to toughen sanctions and deliver more weapons to repel Russia's attack.
Ukrainian police said there was relentless Russian shelling and air raids in the northeast Kharkiv region, reporting many casualties, while the World Health Organization said there had been several attacks on Ukrainian healthcare facilities.
Moscow maintains its invasion is a "special operation" to capture individuals it regards as dangerous nationalists and to counter what it views as NATO aggression, and has denied targeting civilians.
While men of the conscription age are obliged to stay in Ukraine and help in the defence, mostly women and children have made the often harrowing journey to flee into the European Union.
Officials said many of the refugees who have arrived so far had friends and places to go to but the head of the UN refugee agency told Reuters a growing tide of refugees would put pressure on governments to absorb them.
"Frankly these governments have done very well in their initial response," United Nations High Commissioner for Refugees (UNHCR) Filippo Grandi said in a telephone interview.
"They were well prepared. But if the numbers continue to grow it will be a problem."
Romania has taken in 227,446 Ukrainians, including 31,628 who arrived on Saturday, border police data showed. More than 163,000 entered Hungary since Feb 24.
The Romanian government plans to set up a hub near Suceava airport in the northeast to receive and send out international humanitarian aid to Ukraine.
Slovak Prime Minister Eduard Heger visited the Vysne Nemecke crossing on Saturday night and warned the country needed to prepare for an increasing flow of refugees. Police data showed nearly 114,000 people have crossed into Slovakia so far.
"The amount (of people crossing) are relatively stable and the speed of their handling is high," he told reporters. "But we expect the wave of refugees fleeing the war will grow and it is necessary to prepare for even higher numbers."
