There are now 55 Dutch adults, of whom three-quarters are women, living in Syrian Kurdish camps or in detention, together with 85 children, the Dutch security service AIVD said on Thursday.

Many of the children were born in the region, the AIVD said. A month ago, the AIVD said 40 adults and 65 children were living in Kurdish camps or prisons.

In addition, a further 80 or so Dutch jihadis are still involved in active fighting in the region and they have a further 85 children with them, the AIVD said. Nine in 10 of the children are below the age of nine.

Some 300 Dutch nationals have travelled to the ISIS caliphate, of whom 90 have died and 60 returned to the Netherlands.

The Dutch government remains adamant that it will not act to bring Dutch jihadis back to the Netherlands, despite a plea by the children’s ombudsman earlier this year to help the children to return.

Dutch jihadis can currently only return to the Netherlands if they manage to get to a Dutch embassy or consulate under their own steam.