Groups such as Islamic State will not shrink from using children in terrorist attacks in Europe and children returning to the Netherlands from IS areas should be seen as posing a potential threat, the Dutch counter terrorism unit said on Thursday.

IS already uses children in attacks in Syria and Iraq because they are viewed as less dangerous and can slip more easily through controls, the NCTV says in a new report.

Children ‘should be seen as victims of IS, without losing sight of the possible threats they pose to society,’ the report states. They may also be extremely traumatised because of the bloodshed they have witnessed, the new report says.

Although few families with children are returning at present, more will return to the Netherlands as the region held by IS continues to shrink, the organisation predicts. The NCTV says at least 80 Dutch children are in IS-held territory but the true number is likely to be higher as more babies are born to Dutch parents.

On returning to the Netherlands, children should have to undergo a DNA test to establish if the people claiming to be their parents are related, the NCTV says.

The NCTV and security service AIVD on Thursday published a joint document outlining how IS indoctrinates children and suggesting how social services can help ensure they reintegrate into society.