A teenage Muslim convert who became radicalised online during lockdown was 24 hours away from carrying out a terrorist attack when he was arrested, police have revealed.

Matthew King, 19, carried out reconnaissance on a police station and an army barracks in east London and researched buying knives and a sword on the internet.

After covertly taking photographs of police officers standing outside a magistrates court, King posted a message on Snapchat which read: “Target acquired.”

Commander Dom Murphy from Scotland Yard’s SO15 counter terrorism command said he believed King had been as little as 24 hours away from launching a low sophistication terrorist attack when he was arrested on May 18 last year at his home in Wickford, Essex.

Earlier this year, King admitted one count of preparing a terrorist act and at a hearing at London’s Old Bailey on Friday was sentenced to life with a minimum term of six years.