Wyvern St Edmund's has informed parents that the school is closed due to an 'unforeseen incident'.
The incident that occurred this morning prevented the school from opening.
Staff were altered to a "potential security threat" this morning and informed police.
Read more - TEEN ARRESTED IN CONNECTION WITH SECURITY THREAT
Wiltshire Police officers attended the site to "assess and ensure the safety of the premises" and are expected to remain at the school for several hours.
There is currently no evidence that the threat the school received was real.
Magna Learning Partnership, who runs the school, said: "The Trust emphasises the importance of treating such matters seriously.
"The Trust acknowledges the significant disruption this incident has caused to both students and staff and is treating the matter with utmost seriousness."
Wiltshire Police told Salisbury Radio, "We are working closely with staff at Wyvern St Edmund’s School in Laverstock, which has taken the decision to close today (10/01) as precautionary measure, after receiving a threatening email.
"A search of the school building and grounds is underway to ensure that the premises are safe for pupils and staff before reopening.
"In consultation with the police, parents of pupils will be updated directly by the school with regards to reopening arrangements."
It is hoped the school will reopen tomorrow (Thursday 11th January). Further updates on this will be provided.
Online learning will be sent out to students and parents via the school's Classcharts system. Children will need to log in to their accounts to access the work set.
The message from headteacher Louise Henderson was sent out to parents this morning, and bus companies were also informed.

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