Police are urgently trying to trace Shamima Begum, 15, Kadiza Sultana, 16, and 15-year-old Amira Abase after they flew to Istanbul in Turkey from Gatwick Airport on Tuesday.
The girls, who are all from east London, are pupils at Bethnal Green Academy school and have been described as “straight A students”.
It has been claimed that Aqsa Mahmood, of Pollokshields, Glasgow, who travelled to become a “Jihadi bride” in 2013, had been in touch with one of the three girls on social media, urging her to join the terror group.
In a statement released through their lawyer, the Mahmood family told her: “You are a disgrace to your family and the people of Scotland, your actions are a perverted and evil distortion of Islam.
“You are killing your family every day with your actions, they are begging you stop if you ever loved them.”
Scotland Yard revealed the three missing girls were previously spoken to by officers investigating the disappearance of a fellow pupil – a 15-year-old girl – who fled to Syria in December.
But there was “nothing to suggest at the time” that the trio were at risk and their disappearance has “come as a great surprise, not least to their own families”, a spokesman said.
The girls left their homes before 8am on Tuesday providing their families with “plausible” reasons as to why they would be out for the day, police said.
They boarded a Turkish Airlines flight to Istanbul – the airline did not notify police that the girls were on board.
The Muslim Council of Scotland has suggested that more stringent airport checks should be carried out in an effort to stop teenagers from travelling to Syria. Commander Richard Walton, head of the Metropolitan Police’s counter-terror command, has said there was a “good chance” the girls were still in Turkey and hoped that a police appeal would persuade them not to enter Syria.
Relatives of the three missing schoolgirls have pleaded for them to return home.
Amira’s family said: “Amira, We miss you so much, everyone, your family and your friends. We want you to come home as soon as possible. All we are hoping for is you to come home safe, we love you so much.
“Please come home Amira, everyone is missing you. You are strong, smart, beautiful and we are hoping you will make the right decision. We miss you more that you can imagine. We are worried and we want you to think about what you have left behind.
“You had a bright future, so please return home.”
In a direct message to Shamima, her family said they understood she had “strong feelings” about people she believed were suffering in war-torn Syria but warned it was a “dangerous place”.
They said: “Syria is a dangerous place and we don’t want you to go there.
“Get in touch with the police and they will help to bring you home. You are not in any trouble.
“Please don’t cross the border. Please come home to us. Our mum needs you home and is really worried. We are not mad at you, we love you.”
Meanwhile, Kadiza’s family said they were “completely distressed” and were praying for the girls’ safe return.
They said: “In your absence, we, as a family, are feeling completely distressed and cannot make sense of why you left home. Due to the speculation that you may be travelling towards Syria, we are extremely worried about your safety.
“As time progresses, our concerns are increasing more and more. We just want you all to return home, safe and sound.”
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