More than 1.5 million children fled Ukraine after Russia’s attack. The agency claims that a child is almost every second a refugee from war.

“The war in Ukraine has led to massive displacement and refugee flow — conditions which could lead to an acute child protection crisis and a significant spike of human trafficking,” UNICEF’s Regional Director, Europe and Central Asia, said in a statement Saturday.

UNICEF reported that more than 500 children unaccompanied crossed from Ukraine to Romania between February 24th and March 17th. However, the number of separated children fleeing may be much greater. According to the United Nations , more that 3 million people had fled Ukraine in 20 days.

UNICEF says that separated children are particularly vulnerable to trafficking or exploitation.

UNICEF and Inter-Agency Coordination Group Against Trafficking recently found that 28% are children. UNICEF officials stated that they believe Ukrainian children account for an even greater percentage of the global trafficking victims because of the fact that children and women fleeing Ukraine make up almost all of the global population.

UNICEF urges countries that are welcoming refugees to increase their child protection screenings at borders. It also emphasizes Ukraine’s neighboring countries. UNICEF also encourages countries and child protection authorities from different countries to work together across borders to increase screening at refugee camps and other areas where they are most likely to travel.

Khan stated that children fleeing war in Ukraine should be screened to determine their vulnerability before crossing into neighboring countries. Khan stated that it was important to improve screening at refugee border crossings.

The U.N. Migration Agency Mission is asking to receive monetary donations in order to provide assistance to both refugees fleeing Ukraine and those who have been internally displaced.