A British teenager has pleaded guilty to sending bomb threats to thousands of schools and a United Airlines flight.
George Duke-Cohan, 19, admitted making the threats to UK schools last March, causing 400 of them to be evacuated.
Speaking to the perpetrator at the time, Sky News learned that the emails were spoofed to look like they had been sent by Minecraft gaming network VeltPvP due to the hoaxer's feud with the group.
However, following the media attention paid to the hoaxes, Duke-Cohan, from Watford in Hertfordshire, continued to send hoax threats to a number of victims.
He was arrested just days after sending the hoax emails, but was released on pre-charge bail with conditions restricting his use of technology.
However, according to the National Crime Agency, Duke-Cohan continued to send bomb hoaxes while under investigation, including another mass email to schools in the UK and US claiming pipe bombs had been planted on their premises.
The agency added that last month, Duke-Cohan or his associates, using the hacker group name Apophis Squad on Twitter, claimed a United Airlines flight had been grounded due to their actions.
The NCA, working with the FBI, stated Duke-Cohan had made bomb threats to the US-bound flight by calling both San Francisco airport and police.
"In a recording of one of the phone calls which was made while the plane was in the air, he takes on the persona of a worried father and claims his daughter contacted him from the flight to say it had been hijacked by gunmen, one of whom had a bomb," the NCA said.
When the plane landed it was held in a quarantined area of the airport, and all 295 passengers were forced to remain aboard - disrupting their travel plans and causing financial damage to the airline.
Duke-Cohan was arrested for a third time at his home in Watford on 31 August, when the police found multiple electronic devices which he was banned from using.
The NCA's senior investigating officer Marc Horsfall 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."