A teenager has confessed to plotting a terror attack in London that could've resulted in hundreds of deaths.
19-year-old Haroon Syed plead guilty on Thursday at the Old Bailey to researching, planning and attempting to source materials for homemade explosive devices.
Potential targets included Buckingham Palace and an Elton John concert, taking place on an anniversary of 9/11.
Syed had attempted to get a bomb vest online to use in some of the busiest areas of the capital.
Elton John at his Hyde Park concert last September. Image: PA
He was caught out by officers from the British Security Service who had posed as extremists online.
Syed, from Hounslow in west London, is yet to be sentenced though judge Michael Topolski warned the teenager his ploy was "a grave offence, and he would consider if a life sentence was merited."
His elder brother Nadir, 24, was convicted and sentenced to life in prison last year after plotting to behead a poppy-seller on Remembrance Sunday.
Syed had been contacting fake profile Abu Yusuf via mobile and social media requesting the "gear" he would need for his "opp".
The defendant said he need a machine gun and an explosive vest "so after some damage with machine gun do martyrdom. That's what I'm planning to do."
He added: "You have to find out the price for a machine gun, any gun."
Although hesitant to meet up with Yusuf after complaning that police were following him, the two finally met at a Costa Cofee in Slough. The undercover officer taped the entire thing.
For a month the conversations continued.
On August 30, Syed asked if he could gather a portable device, saying: "I might put the bomb in the train and then I'm going to jump out so the bomb explodes on the train ... So ask the brother if he can make that type of bomb with button."
The following week he arranged to pick up the bomb for the price of £150.
He asked Yusuf to put as many nail in it as he could. "I was thinking of Oxford Street ... If I go to prison, I go to prison. If I die, I die, you understand?" he said.
Police eventually raided the home of the defendant and arrested him on September 8, 2016. When asked for the password to unlock his phone, Syed said: "Yeah I.S.I.S - you like that?"