The United Nations’ refugee agency says more than five million Ukrainians have been forced to flee their country in less than two months since the Russian invasion, creating an unprecedented refugee crisis.

The Geneva-based UN High Commissioner for Refugees (UNHCR) on Wednesday said 5.01 million Ukrainians had left the country since Russia invaded on February 24.

The figure of five million is a fresh and “staggering” milestone in Europe’s biggest refugee crisis since World War II as the onslaught intensifies in the eastern Donbas region.