Those held in the al-Hol displacement camp run by Syrian Kurdish forces come from some 60 countries. They fled IS’s final enclaves, and the majority of them are Iraqi or Syrian.

“The tens and thousands of children stranded in Al Hol, other camps and detained in prisons are victims. They are victims no matter what they or their parents might have done or stand accused of,” ICRC President Peter Maurer said in a statement after visiting the sprawling site where it runs a field hospital and provides food and water.

Children, many orphaned or separated from their parents, are growing up in often dangerous conditions in the camp, he said. In January, the United Nations said it had received reports of 12 Syrian and Iraqi nationals being murdered there.

Maurer urged authorities to end a “tragedy in plain sight”, adding: “Positive examples of repatriation and reintegration do exist”.

Some states have balked at reclaiming their citizens, invoking security concerns, or tried to strip them of their nationality.

Maurer ended a five-day visit to Syria that also included stops in Hassakeh, Daraya outside Damascus, and ministerial-level talks in the capital as the country marks 10 years of war.

President Bashar al-Assad, with the help of Russian and Iranian forces, has all but crushed the insurgency.

U.N. rights experts, in an appeal last month, urged 57 states to repatriate nearly 10,000 of their citizens held in the camps in “sub-human” conditions without legal process.

Under international law, states have a duty to repatriate their citizens and, if there is evidence, to prosecute adults for war crimes or other offences at fair trials in their domestic courts, they said.

Read: Indonesian Children in Syria Need Protection and Repatriation

REUTERS