A judge has imposed a travel ban on a 16-year-old boy whose two brothers were killed fighting in Syria – as he said it is difficult for most people to imagine how parents can have no idea that their children might be planning to travel to war-torn areas of the Middle East for "martyrdom".
Mr Justice Hayden made the teenager a ward of court during a hearing in the Family Division of the High Court in London, after local authority social services staff raised fears that the teenager could travel to Syria.
The teenager, who cannot be named, is not allowed to leave the jurisdiction of England and Wales.
The local authority was named as Brighton and Hove City Council.
Mr Justice Hayden was told that the teenager had joint Libyan and British nationality.
He was told that council staff had learned that family members were making plans for the teenager to go on a trip to Dubai during the Easter holiday.
The judge said he was concerned to "keep this lad alive" and said an order which barred from travelling abroad was proportionate.
"(The teenager) is a vulnerable young person," said the judge.
"He has grown up in modern Britain in an extraordinary family - a family where the male members are patently committed to waging Jihad in war-torn Syria."
He said he had balanced the teenager's human rights and added: "The balance falls clearly in protecting this young man, ultimately from himself."
Lawyers told the judge that the teenager lived with his mother.
Mr Justice Hayden said she was "exhausted by grief" and there were concerns that she was unable to place "proper boundaries" around him.
He said he could understand how children could trick parents by saying they were visiting a friend when they were going a night out.
But he suggested that it was hard to understand how children could trick parents into getting them a passport to travel to countries such as Libya.
"Even when children spend time on the internet in their bedrooms, it is difficult for most people to imagine children growing up in their own households becoming sufficiently radicalised to seek martyrdom without the parents having the faintest sense of it," he said.
"I can understand a child tricking his parents by saying he is going to visit a friend when he is actually going for a night out. But tricking his parents into getting him a passport to go to Libya?"
Mr Justice Hayden said the council had considered asking for the teenager to be taken into care. But given the boy's age, staff thought making him a ward of court would be a better option.
The judge said by becoming a ward of court the youngster would come under the protection of a judge and added: "A child who is a ward of court may not be removed from England and Wales without the court's permission."
Lawyers said it was thought this was the first time a family court judge had been asked to take such an approach to prevent a boy going to fight in Syria.
Additional reporting by Press Association