A 19-year-old man has been given life with a minimum term of six years for planning to stab police and soldiers.
Police believe Matthew King, who converted to extreme Islamism during lockdown, could have been hours away from carrying out an attack when they arrested him.
King will serve a discretionary life sentence of a minimum of six years, minus the 367 days he spent on remand.
The judge praised King’s mother for reporting her suspicions to police.
In January this year, King pleaded guilty at the Old Bailey to the preparation of terrorist acts between December 2021 and 17 May 2022.
Sentencing him on Friday, Judge Mark Lucraft KC said: “When it comes to the minimum term that you will serve, I make it plain that I am not ordering that you are to be released at the end of it.
“Whether you will be released or not at that stage or at any later stage will be a matter for the parole board to consider only when the minimum term has been served.”
Judge Lucraft warned King that if he was released he would remain on licence and liable to recall for the rest of his life.
“In my judgement, you are someone where there is a significant risk to members of the public or serious harm,” the judge told King.
Police believe King turned from being a “troubled young man” to a potential “self-initiated terrorist” while stuck at home during the Covid-19 lockdowns.
Cdr Dominic Murphy, the Met’s head of counter-terrorism, told journalists that King “held really extreme anti-Western views, he had an extremist Islamist mindset and he was intending to carry out a terrorist attack either here or abroad”.
“It was imminent,” Cdr Murphy said.
Prosecuting barrister Paul Jarvis told the court King had dabbled in drugs since early secondary school, was expelled and left education at 16 with no qualifications.
He converted to Islam in 2020 and, at first, his behaviour improved, but in 2021 he began criticising his sisters’ clothing as immodest. His mother contacted the government anti-extremism agency, Prevent, because she feared the videos he was watching promoted hatred.
Officers from the Metropolitan Police arrested King at his home at Wickford in Essex on 18 May last year.
Examination of his phone revealed evidence of him viewing extremist videos which officers believe had convinced him he should kill or torture a British soldier either in the UK or abroad.
The phone also showed he had joined an online chat group where he discussed terrorist funding and travel routes to Syria.
He had changed his WhatsApp status to “kill non-Muslims” and recorded himself rapping to his own lyrics about fellow terrorists in Belmarsh Prison and detonating a bomb, officers found.
In 2022, in the weeks before his arrest, King began carrying out reconnaissance in east London, including on police officers patrolling outside Stratford railway station, as well as at Stratford police station and magistrates’ court.
Mr Jarvis told the court that among videos found on his phone was one near the police station, overlaid with a soundtrack including the words: “Coldly kill them with hate and rage. Plan your perfect killing spree.”
On 17 May 2022, a CCTV camera had captured him filming after dark outside the 7 Rifles army barracks in east London.
He had also purchased military goggles and gloves, and carried a balaclava and a “shihada” jihadist flag, sometimes wearing combat clothing to the mosque.
Several of the mosques he attended warned him several times about his behaviour, and one decided he was no longer welcome, Mr Jarvis told the court.
Members of the public who called the police about King included members of two WhatsApp groups he had joined called Southend Brothers and Southend Shurah.
King was put under surveillance, and his social media posts of police officers, captioned with the words “Target Acquired”, heightened concerns at how fast he appeared to be moving towards an attack. These concerns led to his arrest.
Evidence of King’s efforts to buy a hunting knife online helped police build the case against him – he had to give passport details to prove his age, under new rules brought in since 2019.
Although King never bought a weapon, police say he would have easily been able to obtain a kitchen knife to carry out attacks, though potential terrorists often prefer bigger hunting knives for their shock factor.
Officers also obtained Snapchat messages King sent to a girl who was still in the sixth form, in which he said he wanted to travel to Syria to become a martyr.
They exchanged messages about how they would like to mutilate members of the British and American armed forces.
Miss A wrote to him: “We can’t let them die quick tho. Slow painful death akhi… I’ll guide you through it. Or bring him or her home.”
He said he was “training for Jihad” and just wanted “to kill people”.
Mr Jarvis told the court that on 17 May 2022, the day before King’s arrest, the girl messaged him to say she wanted to concentrate on her exams. King replied he would “be worshipping Allah” and he might soon be “on the news”.
