Over 100 convicted terrorists could be set free from prison and released onto British streets as soon as next month, despite the UK recently upgrading the terror threat to the second-highest level following the recent spate of Islamist attacks across Europe.

One of the terrorists considered likely to be released is a teenage ISIS supporter who was found guilty of plotting a police beheading when he was 14 years old. The convicted terrorist is now 20; however, it is believed that he is still residing in a youth jail.

The terrorist, known as RXG — after the High Court granted him anonymity for life — became eligible to receive parole last month. Despite being handed a life sentence in 2015, he was only ordered to serve a minimum of five years in prison, as life sentences in Britain seldom are for life.

A parole hearing for RXG is set for early December after the national lockdown in England is expected to be lifted. According to court papers seen by The Times, the likelihood of the terrorist being freed is believed to be high.

Other terrorists who could be released include two men who travelled to Syria to receive weapons training, a man who tried to join ISIS and wed a nine-year-old girl, and a man who downloaded assassination manuals from a terrorist group.

It follows the release of Britain’s first al-Qaeda-inspired terrorist, Moinul Abedin, who was quietly released from prison in February, after serving 18 years for collecting almost some 200lbs of bomb-making chemicals in Birmingham.

In February, the government passed the Terrorist Offenders (Restriction of Early Release) Bill, which sought to prevent the early release of terrorists. The legislation followed the Streatham knife attack, in which a convicted terrorist, Sudesh Amman, who was released after only serving half of his sentence, stabbed two people, days after his release.

The update to the law mandates that terrorists serve at least two-thirds of their prison sentence and be subjected to a review by a parole board before being released, compared to the half-term that is mandated for most criminals.

The change in the law has apparently done little to stop parole boards freeing terrorists before their full sentences are served. Over the weekend, officials disclosed that 110 have now served the two-thirds of their term required to be considered for release.

One of those terrorists to have reached the threshold is Yusuf Sawar, who was sentenced to 12 years and eight months after he was found to have travelled to Syria to join jihadists in 2013. His parole hearing is set to take place in January.

A Parole Board spokesman claimed that representatives for the body receive “rigorous training” for dealing with terrorism cases and that those deemed to be a risk to the public will not be released.

“Parole reviews are undertaken thoroughly and with extreme care. Protecting the public is our No 1 priority,” the spokesman said.

On Tuesday, Home Secretary Priti Patel revealed that the Joint Terrorism Analysis Centre (Jtac) upgraded the terror threat in the UK to Severe, meaning that a terror attack is “highly likely“.

The announcement followed weeks of terror attacks across continental Europe, starting with the beheading of French teacher Samuel Paty, by a Chechen refugee. The 18-year-old jihadist was reportedly enraged over the teacher showing caricatures of the Muslim prophet Mohammed by the French satirical magazine Charlie Hebdo to his class during a lesson on freedom of expression.

Following the outrage over President Emmanuel Macron’s defence of the magazine’s right to free speech, terrorist attacks took place in Nice,  Lyon, and in Vienna, where an Islamist gunman killed four and injured 17 more before being shot dead by Austrian police.

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