I have no sympathy towards Shamima Begum for joining Isis. However, I do have serious concerns as to how our society allowed this to happen. And as speculation grows over whether she will now be prosecuted at home – despite government commitments to strip her of her citizenship – that is still not clear.

In December 2014, 15-year-old Sharmeena Begum was the first London schoolgirl who left to go to Syria. Her father, Mohammed Uddin, was so concerned about her friends that he informed the police and the asked school to keep an eye on her friends. But in February 2015, friends Amira Abase, 15, Shamima Begum, 15, and Kadiza Sultana, 16, ran away to Syria.

The case of Shamima Begum is under discussion again this week as it emerged that journalists who met and interviewed the young Isis recruit inside a refugee camp have been asked to turn over their full notes to Scotland Yard. Begum’s family lawyer, Tasnime Akunjee, believes this is because UK police are now “building a case against her”.

When the girls first left for Syria, I was a senior portfolio-holding councillor in Tower Hamlets. By June 2015 I had become a backbencher, but I never stopped asking myself what led these schoolgirls to leave for a place devastated by conflict and death.

In July 2015, I brought a motion to council suggesting a new way in which Tower Hamlets could safeguard children and young people from radicalisation. Earlier this year I again proposed a motion for extra resources for safeguarding against radicalisation. I do not flinch from continuing to ask the questions that many seem not to want to answer. I am still determined to discover what happened so that we can learn from this situation and take steps to prevent it from happening in the future.

Timeline of the Isis caliphate Show all 19 1 /19 Timeline of the Isis caliphate Timeline of the Isis caliphate ISIS began as a group by the merging of extremist organisations ISI and al-Nusra in 2013. Following clashes, Syrian rebels captured the ISIS headquarters in Aleppo in January 2014 (pictured) AFP/Getty Timeline of the Isis caliphate Abu Bakr Al-Baghdadi declared the creation of a caliphate in Mosul on 27 June 2014 Timeline of the Isis caliphate Isis conquered the Kurdish towns of Sinjar and Zumar in August 2014, forcing thousands of civilians to flee their homes. Pictured are a group of Yazidi Kurds who have fled Rex Timeline of the Isis caliphate On September 2 2014 Isis released a video depicting the beheading of US journalist Steven Sotloff. On September 13 they released another video showing the execution of British aid worker David Haines Timeline of the Isis caliphate The US launched its first airstrikes against Isis in Syria on 23 September 2014. Here Lt Gen William C Mayville Jnr speaks about the bombing campaign in the wake of the first strikes Getty Timeline of the Isis caliphate Isis militants sit atop a hill planted with their flag in the Syrian town of Kobani on 6 October 2014. They had been advancing on Kobani since mid-September and by now was in control of the city’s entrance and exit points AFP/Getty Timeline of the Isis caliphate Residents of the border village of Alizar keep guard day and night as they wait in fear of mortar fire from Isis who have occupied the nearby city of Kobani Getty Timeline of the Isis caliphate Smoke rises following a US airstrike on Kobani, 28 October 2014 AFP/Getty Timeline of the Isis caliphate YPG fighters raise a flag as they reclaim Kobani on 26 January 2015 VOA Timeline of the Isis caliphate Isis seized the ancient Syrian city of Palmyra on 20 May 2015. This image show the city from above days after its capture by Isis Getty Timeline of the Isis caliphate Kurdish forces are stationed on a hill above the town of Sinjar as smoke rises following US airstrikes on 12 November 2015 AFP/Getty Timeline of the Isis caliphate Kurdish forces enter Sinjar after seizing it from Isis control on 13 November 2015 AFP/Getty Timeline of the Isis caliphate Iraqi government forces make the victory sign as they retake the city of Fallujah from ISIS on 26 June 2016 Getty Timeline of the Isis caliphate Iraqi forces battle with Isis for the city of Mosul on 30 June 2017 AFP/Getty Timeline of the Isis caliphate Members of the Iraqi federal police raise flags in Mosul on 8 July 2017. On the following day, Iraqi prime minister Haider Al Abadi declares victory over Isis in Mosul Getty Timeline of the Isis caliphate Members of Syrian Democratic Forces celebrate in Al-Naim square after taking back the city of Raqqa from Isis. US-backed Syrian forces declare victory over Isis in Raqqa on 20 October 2017 after a four-month long campaign Getty Timeline of the Isis caliphate Female fighters of the Syrian Democratic Forces celebrate in Al-Naim Square after taking back the city of Raqqa from Isis. US-backed Syrian forces declare victory over Isis in Raqqa on 20 October 2017 after a four-month long campaign AFP/Getty Timeline of the Isis caliphate Trucks full of women and children arrive from the last Isis-held areas in Deir ez-Zor, Syria in January 2019 They were among the last civilians to be living in the ISIS caliphate, by this time reduced to just two small villages in Syria’s Deir ez-Zor Richard Hall/The Independent Timeline of the Isis caliphate Zikia Ibrahim, 28, with her two-year-old son and 8-month-old daughter, after fleeing the Isis caliphate, on Saturday 26 January 2019 Richard Hall/The Independent

With most of the focus on Shamima Begum, it is often forgotten that a total of nine girls tried to flee to Syria; four of them, including Shamima, succeeded and joined Isis, while five girls were made wards of court and prevented from travelling. Alarmingly, all nine of these girls attended the same school − Bethnal Green Academy.

How did Isis manage to lure nine girls from the same school? Who had easy access to nine schoolgirls to radicalise them? Is this only happening Tower Hamlets, or elsewhere? Our community has still not been provided with an explanation.

Tasnime Akunjee has himself questioned what failures took place that could allow teenage girls to evade the police and security services and make their way into a terrorist-occupied territory. So why has Tower Hamlets council still failed, four years later, to conduct serious case reviews into these incidents? It is the most remarkable and alarming dereliction of the council’s public duty.

The Counter Terrorism and Security Act 2015 contains a duty on specified authorities (local authorities, education providers, health sector, police, prisons) to have due regard for the need to prevent people from being drawn into terrorism. This is the origin of the government’s Prevent strategy. It is therefore the responsibility of all institutions to help identify those and risk. Counter-terror chief Neil Basu says policing alone cannot beat extremism. He said that “up to 80 per cent of those who wanted to attack the UK were British-born or raised, which strongly indicated domestic social issues were among the root causes”.

The excuse that Tower Hamlets has given in a public statement for its failures is that “this case did not meet the threshold for a serious case review”. If schoolgirls bunking off to join a depraved terrorist group threatening the stability of a whole geopolitical region does not meet the threshold, what possibly could? ​In a press statement Akunjee described the situation as “either severe negligence or a cover-up”.

I fully appreciate the need for the security services to keep certain details and evidence confidential, but as a society we cannot allow crucial facts to be hidden. We cannot act after the event. Prevention is far better than having to deal with the aftermath. If parents are not aware of how the radicalisation of the Bethnal Green girls happened in the first place, they cannot help prevent other young people from being radicalised too.

No child goes to sleep one night, then wakes up the following morning a radical theist. Radicalisation can be a very quick process – perhaps occurring over only a matter of weeks – but there is still sufficient time that it should have been spotted. Our society has failed these girls because we did not prevent this process from happening.

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Nine girls, one school: Bethnal Green Academy. What was it that made these students vulnerable to radicalisation? Did they experience discrimination, have family issues, have low self-esteem or question their place in society?

Shamima the adult is now paying for the mistake made by Shamima the girl. Is that fair? It’s a complex question. Everyone makes mistakes when they are growing up – some worse than others. Sadly, she made a colossal error of judgement in joining Isis and we cannot know now whether she understood the consequences of doing so. From my own perspective, I suspect she did not.

When pleading to return to the UK, she claimed to have been “brainwashed” by Isis. Nevertheless, even though she was begging to return to the UK, she said she did not regret going to Syria, though she also claimed not to agree with everything the group had done.

This case has to be one of the biggest failures of the Prevent strategy and of the local authority. Is the blame simply being placed on the individual because that is the easiest thing to do?

In 2015, the real shock of the so-called Bethnal Green Brides was that schoolchildren had been influenced by Isis propaganda so significantly that they were prepared to make such a drastic decision and gamble with their lives. In my local community, that sense of shock has not gone away.

The majority of the British public would agree with me in utterly condemning anyone – regardless of age or motivation – who betrays their country by fleeing to Isis and supporting the actions of terrorists. But as a society, we need to understand precisely how nine girls from my borough became radicalised.