An estimated 2.3 million people have fled Ukraine as of Thursday, including 1 million children, according to UNICEF.
Most have fled to neighboring countries Poland, Hungary, Slovakia, Moldova and Romania. Nearly 1.5 million Ukrainian refugees have fled to Poland, the U.N. High Commissioner for Refugees reported Thursday.
"The number of children on the move is staggering, an indication of how desperate the situation for children and families in Ukraine has become," said Afshan Khan, UNICEF regional director for Europe and Central Asia. "Children are leaving everything they know behind in search of safety. This is heartbreaking."
RUSSIA ATTACKS UKRAINE: LIVE UPDATES
Ukrainian President Volodymyr Zelenskyy and Ukraine's Ministry of Foreign Affairs said Thursday that Russian military forces shelled a children's hospital and maternity ward, which Russian officials denied.
Zelenskyy said the airstrike on the hospital left three people dead, including a child, and more than a dozen injured.
UKRAINE'S ORPHANS ARE TOP OF MIND FOR ADOPTIVE DAD AND HIS ORGANIZATION
The Office of the U.N. High Commissioner for Human Rights (OHCHR) estimates that a total of 41 Ukrainian children have been killed since Feb. 24 when Russia invaded, but Ukraine's Commissioner for Human Rights Verkhovna Rada is saying that a higher number of children have been killed, 71, and more than 100 injured as of Thursday.
The U.N. humanitarian organization has deployed six trucks carrying nearly 70 tons of supplies, including protection equipment, medical supplies and surgical and obstetric kits, to Ukraine.
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UNICEF will be delivering medical supplies to 22 hospitals in five different war zones to benefit 20,000 children and mothers.