A 15-year-old girl has fled to Syria to fight alongside ISIS. This is her dad's heartbreaking message.

What would you do if you learned your teenage daughter had run away, and was headed to the Middle East to fight alongside ISIS?

One London father, whose 15-year-old daughter is thought to have become radicalised by ISIS through social media, has found himself in just that situation.

And now, he has urged his daughter to come home in a heartbreaking plea video, The Guardian reports.

It’s feared that Hussen Abase’s daughter, Amira Abase, is on her way to fight alongside the Islamic State after she and schoolmates Shamima Begum, 15 and Kadiza Sultana, 16, were captured on CCTV boarding a flight from London to  Istanbul on 17 February.

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“We are depressed, and it’s very stressful. The message we have for Amira is to get back home,” Hussen Abase said in a video intended to reach his daughter. “We miss you. We cannot stop crying. Please think twice. Don’t go to Syria.”

The devastated father also revealed that on the day of her disappearance, the girl had told him she was going to a wedding.

Abase says that there were “no sign to suspect her at all”.

Amira never talked of her plans of Jihad according to her father, who said: “She doesn’t dare discuss something like this with us. She knows what the answer would be.”

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In another video, Shamima’s sister Renu Begum tearfully begs her sister to come home.

“We love her and she’s our baby. We don’t want her to do anything stupid,” she said. “She’s a sensible girl. We’re hoping she wouldn’t do anything that’s going to put her in any danger. We want her and her friends to be safe.”

The videos have emerged as British counter-terror agencies face criticism for their lack of intervention in this case.

Shamima Begum is believed to have been talking online to Aqsa Mahmood – a Scottish woman who left Britain to marry a fighter in 2013; A Twitter exchange between the pair sees ISIS bride Aqsa, who is believed to be under surveillance by British counter terrorist agencies, write to Begum: “follow me so i can dm you back”.

However, the contact apparently went unnoticed by Scotland Yard and other counter-terror agencies.

The Guardian reports that Mahmood’s family lawyer has spoken out against the intelligence agencies, saying the family was “incredulous” nothing was done to stop the schoolgirls’ escape following their contact with Ms Mahmood, a known ISIS supporter.

“The fact that these three girls managed to reach the airport – the common sense approach of Special Branch at the airport, the UK border agencies, don’t notice the fact that two 15-year-olds [and] a 16-year-old are unaccompanied, going on a flight to Turkey, the staging post to Syria, which is what Aqsa did herself and they aren’t stopped,” he told the BBC.

“Obviously the family are deeply distressed and angry and they want answers because they’re thinking ‘how many other families is this happening to?’”

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The British schoolgirls are the latest in a string of youth radicalised after coming into contact with extremists online.

Often, young fighters and potential ISIS brides are recruited via social media, as Mamamia previously reported.

Last year, Austrian girls Samra Kesinovic, 16, and Sabina Selimovic, 15, became radicalised after coming into contact with Chechen youths and fled to Syria, leaving a note telling their horrified families they had gone “to fight for Islam”.

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Watch Hussen Abase’s video message to his daughter:

 Shamima’s sister Renu Begum tearfully begs her sister to come home in this video:

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