The then 16-year-old, who cannot be named for legal reasons, arrived at a secondary school in Bedfordshire at around 1.40pm on May 2 armed with a kitchen knife hidden in a bag.
Two ambulance service workers have been arrested as part of a major investigation into six deaths in Wiltshire.
Gregory Twigg, 32, killed Lee Woodward with three 'powerful and cowardly' punches in a drink and drug-fuelled rage, a court heard.
He 'catfished' his victims into believing he was a 14-year-old boy.
Two teenage sisters were found inside a refrigerated lorry with the temperature below freezing after their half-brother crashed the vehicle.
The criminal gang are due to be sentenced in January.
'They thought that acting quickly and escaping in high-powered vehicles meant that they were above the law. They were wrong.'
The youngster was heading from the city centre to the airport when the attacked happened on June 5.
Pernilla Sjoholm has turned from a victim into a scam fighter.
United News - unews.co.za