Dozens of school across Britain were placed on lock-down today after receiving imminent threats of an attack on students.
The email, which is now being treated as a hoax, claimed a car would mow down as many pupils as possible leaving the schools.
If children were to be evacuated from the premises, they would be shot, the email added.
Anxious parents were reportedly outside schools picking up their children after the threats were made.
The email read: ‘If you try and evacuate them the driver will get out and shoot any student leaving. You have a choice here, you can ignore this email and risk the lives of the students you say you care for, or you can listen to what we are telling you.
‘The only way out is to go out with a BANG.’
A marked police car would be stationed outside Heronsgate primary school and neighbourhood policing teams would visit the school in the next few days, the headteacher warned
It finished: ‘From your team PI3x13t.’
Schools from the North East to the South West of England were threatened by the hoax today, which the National Crime Agency has now been enlisted to work alongside police force in the affected regions.
The Metropolitan Police confirmed there were a ‘number of reports’ that the hoax email had been sent to schools in London.
A spokesman for the Metropolitan Police said: ‘The Met has received a number of reports relating to malicious communications sent to schools across London on Wednesday, 28 March.
‘These are currently being treated as hoaxes. There is no evidence to suggest that this is terror-related.’
One of the schools in London which was forced to evacuate was Heronsgate Primary School in Greenwich.
A marked police car would be stationed outside the school and neighbourhood policing teams would visit the school in the next few days, the headteacher warned.
Steven Connors added: ‘We evacuated both sites to ensure the safety of the children,’ said the letter.
‘We responded quickly to the threats and made the Police aware.
‘The Metropolitan Police have advised that they are not treating the emails as a credible threat.
‘There is nothing within the email that names a specific school and the same email has also been sent to other schools throughout London.
Plymouth City College was among the schools to have a hoax attack threat made to it today
‘The children were extremely well behaved and co-operated fully.’
One school in Colchester for autistic children had to close following the threat.
Doucecroft School at Eight Ash Green, near Colchester, is owned and operated by Autism Anglia and includes pupils from Essex and the surrounding area. Staff contacted parents to come and collect their children after the threatening phone call earlier in the day.
The school caters for day and and residential pupils. A number of day pupils who were due to stay overnight had to be taken home and others in the residential area of the school had to be evacuated.
One parent, whose child has to travel 25 miles from their home in Suffolk every day, said: ‘We don’t have any details yet but what kind of sick individual would target children like this who are among the most vulnerable in society.’
At least 12 schools in Plymouth received the hoax email, including Marlborough Primary school and Plymouth City College.
Headteacher of Plymouth’s Marlborough Primary School, Rachel Summers said: ‘We followed procedure by phoning 999, phoning the police, as soon as we received that email – and then went into lockdown, so that children were all inside, with doors locked, nobody in, nobody out, just to be safe and make sure children were OK.’
A spokesperson for Devon and Cornwall Police said: ‘We are aware of a series of malicious communications to schools in Devon and Cornwall as well as across the country.
‘Enquiries continue to establish the facts and forces are working together to investigate who is responsible.
‘Police take hoaxes extremely seriously. They divert police resources and cause disruption and alarm to the public.’
The Milton Primary school was among one of three to be evacuated in Stoke-on-Trent
Suffolk Police confirmed it received 14 reports of a ‘malicious hoax’ to schools today.
A spokesman added: ‘Officers take hoaxes extremely seriously. They divert police resources and cause disruption and alarm to the public.
‘Suffolk County Council is working to support police and the affected schools.’
A further six schools in Cheshire also got received the email, as well as schools in Birmingham, Cambridgeshire, the North East and in Stoke.
The Milton Primary school was among one of three to be evacuated in Stoke-on-Trent.
Chief Inspector Catherine Clarke, from Durham Constabulary, said: ‘We can confirm that at this time we believe none of the threats received by schools to date are considered to be credible.
‘In the absence of any further threats being received, schools do not need to take any further action.
‘If any further threats are received they should be reported immediately to police.
‘We are in contact with the schools in our area to give guidance and reassurance.
‘More than 100 schools in the North-East region have received the emails and we are working with neighbouring forces to establish the facts and investigate who is responsible.’
It comes two weeks after similar letters were sent to schools threatening to detonate bombs left on school property throughout the UK.
Police later announced that they did not believe the threat to be viable, as the letters had been sent from the United States and were demanding money.