A school in east Belfast will remain closed today as the PSNI investigate a threat received by email.

Elmgrove Primary School received the threat, and last night a man (33) was arrested in relation to the investigation.

The school is in a mainly unionist area of Belfast. The threat was received by the school on Wednesday.

Naomi Long, Alliance Party MP for Belfast East, tweeted yesterday, before the arrest was made:

"For parents of children at Elmgrove Primary School, PSNI have confirmed a threat was received by school via email from an individual."

"The Board and school have decided to close the school tomorrow as precaution. Extra police are in the area to provide reassurance to lical (sic) residents & active investigation underway."

Alan Murray is a security journalist in Belfast. He says parents were concerned that they only learned about the threat yesterday.