Duke-Cohan, of Mutchetts Close, caused widespread panic between 16 March and 19 March this year, when he emailed more than 1,700 schools, colleges and nurseries across the UK to warn about an explosive pipe bombs. Four Hundred of the schools were evacuated.
George Duke-Cohan, 19, sparked nationwide panic from the bedroom of his home in Watford.
He was linked to a cyber-hacker group on Twitter calling itself the Apophis Squad.
Schools in London, Manchester and North Yorkshire were among those that received the email.
The email threat is written in both English and Arabic.
Other emails claimed pipe bombs were hidden on schools' premises and a car would be driven at students at home-time.
whilst on bail Duke-Cohan called San Francisco airport posing as the concerned father of a girl on board United Airlines flight UAL 949, claiming hijackers had taken over the flight from Heathrow to San Francisco.
Duke-Cohan was arrested for a third time on 31 August.
He was sentenced to one year in jail for the emails sent to schools and two years for the airport security scare.
Judge Foster said that, for the purposes of sentencing, he accepted Duke-Cohan had autism spectrum disorder.
Following the conviction, Marc Horsfall, the NCA's senior investigating officer, said: “George Duke-Cohan made a series of bomb threats that caused serious worry and inconvenience to thousands of people, not least an international airline.
“He carried out these threats hidden behind a computer screen for his own enjoyment, with no consideration for the effect he was having on others.
“Despite being arrested and having conditions imposed restricting his use of technology, he persistently broke those conditions to continue his wave of violent threats.
“Law enforcement take such offences extremely seriously. The sentence handed down to Duke-Cohan today highlights the consequences of such offending."
Thanks for stopping by. We welcome your comments.