UNICEF says of the 1.4 million who fled violence between the army and a local militia central Democratic Republic of Congo, 850,000 are children.
UNICEF said that the children who fled the ravaged Kasai region, have been left prey to attack, detention, sexual violence, and recruitment by militia fighters.
UN says no fewer than 3,300 people have been killed in Kasai since the start of an insurrection in August by the Kamuina Nsapu militia, which wants the withdrawal of military forces from the area.
Kasai is the scene of a growing humanitarian disaster in a nation where violence has spiralled since President
Joseph Kabila refused to step down when his mandate ended in December.
“The crisis is having a devastating impact on children,” UNICEF representative Tajudeen Oyewale said in a statement.
“The lives of hundreds of thousands of children and their families in Kasai have been turned upside down by this brutal violence.”
Oyewale added that the violence had disrupted access to healthcare and education in Kasai, which UNICEF described as one of the world’s worst displacement crises for children.
No fewer than 5,000 children in the region have been separated from their families, and at least 100 were killed in the first three months of the year.
UNICEF said about half of militia members are estimated to be children, many younger than 15, and more than 500 have been deployed as fighters or used as human shields.
“The future of an entire generation of children is at risk in the Kasai region,” added Oyewale.
The violence in Kasai has stoked fears of a wider conflict in the central African giant, a tinderbox of ethnic rivalry and competing claims over mineral resources.
Wars at the turn of the century killed millions and sucked in neighbouring countries.
Some 3.8 million Congolese are uprooted within the country, more than in any other African country, and about 7.3 million need aid urgently, according to UN data.
UN on Wednesday named three experts to lead an international investigation into killings and other crimes in Kasai, having accused “elements” of Congo’s army of digging most of the dozens of mass graves discovered there in recent months.
The government has repeatedly denied its troops were responsible for the graves.