The families of three London schoolgirls thought to be in Syria have travelled to Turkey to retrace their steps . School friends Shamima Begum , 15 , Kadiza Sultana , 16 , and Amira Abase , 15 , left east London for Turkey last month before crossing into an ISIS-controlled area of Syria . The Bethnal Green Academy pupils are feared to have reached the conflict zone to become so-called 'jihadi brides ' with ISIS . Scroll down for video . Anguish : The families of three missing London schoolgirls have travelled to Turkey to retrace their steps . Questions : The families hope to find clues that may help them find or even contact their daughters . Emotional : The families went to the Istanbul coach station where the teenagers boarded their bus to Syria . On the journey , their families went first to the Istanbul coach station where the teenagers waited 18 hours in the biting February chill for their bus to the Syrian border . There they spoke to a man who unknowingly let the girls in . He told ITV News they were 'smiling as they arrived ' and 'smiling as they left ' . Renu Begum , sister of Shamima , told ITV News : 'This is our next step basically to get the message out to them that we 've followed them all the way out here . We want them to know that we love them . ' Halima Khanom , sister of Kadiza , said : ' I do n't really recognise my sister , the video and the CCTV that we saw . Because this is just not her and we just want to understand her , you know , to find some answers and get some help . ' Abase Hussein , father of Amira , said : ' I do n't know how to explain . I ca n't describe my feelings . I feel like my girl is next to me when I find someone that 's on their last journey who saw them . I feel like my daughter is next to me - that 's the feelings I have . ' Searching for clues : At the bus station , the family spoke to a man who unknowingly let the three girls in . Tears : The families struggle to hide their emotions as they retraced the steps of the London schoolgirls . The families left through the same door as the girls at the bus station , and family lawyer Tasnime Akunjee said : 'Of course they feel responsible for their own children , that goes without saying . 'But the fact is these girls were school children and much of what took place clearly took place at school . Police put a cap on information that they and the school were giving back to the parents . ' The east London schoolgirls flew to Istanbul from Gatwick with Turkish Airlines and now believed to be in based in the Syrian town of Raqqa – the Islamic State 's self-declared capital . Last week it emerged that Sharmeena Begum , 15 , a close friend of the trio and a fellow pupil at Bethnal Green Academy , left Britain before them in December . There are suspicions the trio kept in touch with Sharmeena who passed on information about how to follow in her footsteps . Those closest to all four girls suspect they were groomed by Islamists using social networking sites and secretive internet messaging software . The families have criticised police and others for failing to stop them . But their plight has raised questions about why the families themselves did not spot their conversion to radical Islam . Scotland Yard chief Sir Bernard Hogan-Howe has said the three schoolgirls would not face prosecution if they returned home . Familiar route : The families , along with ITV 's Rohit Kachroo , flew in to Istanbul from Gatwick . Looking for answers : By retracing the route of the schoolgirls , the families hope it might bring them home . Elsewhere last week , three British teenage jihadists were placed in custody after a dramatic security operation prevented them joining ISIS in Syria . A pair of 17-year-old schoolboys and a 19-year-old man , all from North-West London , were intercepted in Turkey after their parents realised they had fled to join the terrorist group . They dialled 999 and British police quickly tipped off their Turkish counterparts . Officials swooped on the group within minutes of their flight touching down in Istanbul . Security services say 600 British Muslims have gone to fight in Syria and around 60 of them are young women . They include 22 women and girls who have travelled in the past 12 months , many of whom wanted to become 'jihadi brides ' . ISIS currently controls a swath of land slightly larger than the UK , from Aleppo to central Iraq , and has attracted thousands of foreign fighters to its cause . Turkey has faced criticism for not controlling its border with Syria , but has accused European states of failing to prevent would-be jihadists from leaving in the first place .
Shamima Begum , 16 , Kadiza Sultana , 15 , and Amira Abase , 16 , in Syria . Left east London for Turkey then went into ISIS-controlled part of Syria . Feared to have gone to conflict zone to become 'jihadi brides ' with ISIS . Families have retracted their steps to find clues or even contact with girls . They have previously criticised police and others for not stopping them .