Police have dismissed as a hoax an email sent to schools across the country today, which threatened that pupils would be “run down and shot”.
Investigations have now begun into who sent the emails, which led to some schools being on "lockdown" as frantic parents began arriving to remove children.
A spokeswoman for the Met Police in London said that schools across the capital had been targeted but that the “malicious communications” were being treated as “hoaxes”.
She said there was no evidence to suggest they were terrorist related.
According to The Cambridge Times, an email, signed off “from your team PI3x13t”, told school staff that at 3.15pm a car would drive into as many students as possible as they tried to leave.
It reportedly stated: “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.”
Durham Constabulary said there had been calls from more than 100 schools in the North East region reporting that they had been sent threatening emails.
Chief Inspector Catherine Clarke 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.
“We are working with neighbouring forces to establish the facts and investigate who is responsible.”
Anyone with any information that could assist police should contact on 101, or Crimestoppers anonymously on 0800 555 111.