Safaa Boular, 18, has been sentenced to life imprisonment after becoming the youngest woman ever convicted of plotting a terrorist attack in the UK.

Boular, was already in police custody when the all-female terror cell was exposed in a dramatic raid on Harlesden Road, Willesden. That raid saw her elder sister Rizlaine shot, and accomplice Khawla Barghouthi, arrested.

Safaa Boular was given two life sentences and will serve a minimum of 13 years.

Jailing her for two counts of preparing terrorist acts, Judge Mark Dennis QC told the Old Bailey: “In my view there’s insufficient evidence to say at this stage this defendant is a truly transformed individual.

“Her views were deeply entrenched.

“However much she may have been influenced and drawn into extremism, it appeared she knew what she was doing and acted with open eyes.”

Her mother, 44-year-old Mina Dich, and sister Rizlaine Boular, 22, were locked up in late June, along with accomplice Khawla Barghouthi, 21.

Safaa Boular was sitting her GCSEs when she was seduced online by IS fighter Naweed Hussain, originally from Coventry, who she had planned on joining in Syria.

When she was stopped from doing this, she instead discussed a grenade and gun attack on the British Museum. During her trial, the court heard that while she was in custody the news that Hussain had been killed in a drone strike only served to further radicalise the teenager.

The Met’s Deputy Assistant Commissioner Dean Haydon, Senior National Coordinator for Counter Terrorism Policing said: “This investigation started with Safaa and her attempts to travel out to Syria, marry a Daesh fighter and support their terrorist activity.

“Having been prevented from travelling to Syria, she then set about plotting an attack in the UK but her plans were being covered by the counter terrorism network and security services.

“After Safaa was arrested and charged, her mother and sister tried to pick up where she left off. But again, working with the security services, we tracked their plans and stopped them before they were able to put them into practice.

“All three women were filled with hate and toxic ideology.”

Additional reporting by Press Association.