Dozens of schools have urged parents to pick up their children early today after they received threats that pupils would be run over.

Staff at North Borough Primary School in Peel Street and St Paul's Infant School on Hillary Road in Maidstone both told parents to pick their children up before 2pm, citing a safeguarding issue.

Up to 80 schools are thought to have received an email this morning from someone threatening to drive into pupils at 3.15pm today.

A spokeman for the National Crime Agency, which is leading the investigation said: "We are investigating the source of new threats sent to a large number of UK schools.

"We understand these threats will cause considerable concern but we do not assess them to present an increased risk to the public.

"We are liaising with police forces who are handling local reports."

A police spokesman said: "On Wednesday, police received a number of reports that a threatening email had been sent to schools in Kent. The message is being treated as a hoax with schools across the country receiving similar emails.

"Kent Police take hoaxes extremely seriously and will pursue those responsible. They divert police resources and cause unnecessary disruption and alarm to the public."

Sandling School in Ashburnham Road did not receive the email but has asked parents to pick pupils up early, with other reports coming in nationwide.

St Peter's Primary School in Aylesford, Greenfields Community Primary and independent Shernold School are all thought to have responded.

In Sittingbourne, Meadowfield School in Swanstree Avenue is escorting pupils off site to parents' cars, while there are reports Kemsley Primary School in Coldharbour Lane is also responding to the threat.

Last week a Watford man was arrested after hundreds of schools were closed due to a bomb hoax.