Counter-terrorism officers are hunting for the 15-year-old from Bristol and another girl, a 17-year-old from Lambeth, south London, who flew to Turkey last week in the hope of crossing into Syria.Last night, as her mother Safiya Hussien wept and begged for her safe return, it was claimed the officers fear Yusra could have made contact with a dating site called Jihad Matchmaker.The Daily Mirror was told counter-terrorism officers believe she may have made contact with a Twitter account in the same name, which urges followers to 'picture all the little Mujahideen running around', a number of weeks ago.Citing security sources, the newspaper claimed 'hundreds' of British women have offered to marry jihadis fighting with Islamic State. The English-language Jihad Matchmaker Twitter account, which has just 170 followers, is unverified by any official source and it is not known whether it provides a genuine service to extremists.Despite insisting it is not affiliated to Isis, it urges women to send private messages with their 'age, languages and marital status' and bears the slogan 'keep it halal and get married'.Twitter has vowed to crack down on extremist Twitter accounts but the site remained active last night, despite being set up almost a month ago and being the subject of several online press reports.A police spokesman confirmed yesterday that counter-terrorism officers had taken on the case of Yusra.He added: 'They have strong international links which places them in the best position to pursue the investigation overseas and try to find Yusra and bring her home.'We will continue to work closely with the family and the community in Bristol.'Officers at the South East Counter Terrorism Unit said they too believed Yusra was making her way to Syria - a journey they described as 'extremely dangerous'.'Enquiries by officers identified the 15-year-old from Bristol and the 17-year-old from London are understood to have flown to Istanbul,' said a spokesman.'Officers believe they may be attempting to make their way to Syria.'Officers are providing support to both families and are working to identify where they are and encourage them to return home safely.'Travelling to Syria is extremely dangerous and anyone who is considering travelling to the region is putting themselves at great risk.(dailymail.co.uk)Bakudaily.Az