Police are investigating a series of “malicious” hoax calls made to five schools in West Lothian.
Some schoolchildren have been kept in classes while officers check on the threats believed to have been made against a group of pupils.
The incident is not terror-related and police are said to be following a “positive line of inquiry”.
A force spokesman said: “Police Scotland is investigating after threatening communications were received at schools in the West Lothian and Forth Valley areas on Thursday.
“The threats are of a malicious nature, however local officers are following a positive line of inquiry in an effort to identify whoever is responsible.”
A West Lothian Council spokesman said: “We are aware of these incidents and are working closely with Police Scotland.”
