Terror chief warns of threat from Syria jihadists "The earlier a Muslim family can come to us, the easier it will be to prevent radicalisation occurring," he said. At that point we can work with education, schools and local authorities and support families. It's too late once their youngster is flying back from Syria. Mr Walton confirmed two 17-year-old girls were arrested at Heathrow airport earlier this month over suspected terrorism offences. The pair were later released without charge but the officer said the incident demonstrated how it was not just young Muslim males who were being enticed to join jihad in Syria. "We don't want to alarm the Muslim community that their girls are all going out to fight - they are very small numbers, but nevertheless we can't deny that it is an issue and a concern," he said. A number of teenagers from across Britain had attempted to travel to Syria, he said, adding: "It's shocking they're such young people." Mr Walton, head of the SO15 anti-terror unit, added that wives and girlfriends in Britain could be "complicit" if they failed to tell police about men going to fight in Syria. Most radicalisation was now taking place away from mosques and through the inetrnet, he added.