More than 400,000 Syrian refugee children of school age living in Turkey are not attending school, according to a report by Human Rights Watch, BBC News repots.

The report interviewed 50 families and found that, on average, their children had lost two years of school.

The main issues facing the children are language barriers, financial difficulties and integration problems.

There are around two million Syrian refugees living in Turkey, 708,000 of whom are of school age.

The Turkish government formally granted Syrian children access to public schools in a 2014 policy. One of the barriers facing Syrians is a lack of information about this policy, Human Rights Watch (HRW) says.

"Failing to provide Syrian children with education puts an entire generation at risk," said Stephanie Gee, Bernstein fellow in the refugee rights programme at HRW.

"With no real hope for a better future, desperate Syrian refugees may end up putting their lives on the line to return to Syria or take dangerous journeys to Europe."

The campaign group has called for "urgent financial and technical support" from the international community, warning that failure to act would have "a ruinous effect" on a generation of Syrians.