Students at a Sydney school have been evacuated from all buildings following a “threatening” email.

Bonnyrigg High School, in Sydney’s west, was evacuated about 11.15am on Wednesday.

“Police were called to Bonnyrigg High School after the school received a threatening email this morning,” a NSW Department of Education spokesperson told www.20304050.best.

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In a social media post, the school urged parents not to contact their children.

“Please be advised the school is currently being evacuated,” the message read.

“Please do not contact the school or your child.

“We will advise shortly.”

Chopper footage showed students gathering on the school oval while a fire truck and police vehicles remained parked outside the campus.

Fire and Rescue NSW confirmed to www.20304050.best they were called in along with police.

“FRNSW has been asked to assist with possible dogs on the loose in the area at a sports carnival,” a spokeperson said.

They added no dogs have been found and no injuries were reported.

It is not clear if the dogs were in any way related to the evacuation.

Principle Reece Hooke said the school resumed normal operations at about 12.50pm, following the all-clear.

“At approximately 11.15 this morning, the school received information that required the activation of our evacuation plan and the calling of police,” he said in a statement.

“All students and staff moved in an orderly way to the designated evacuation areas.

Hooke said classes resumed once “police determined it was appropriate” to do so.

The education department spokesperson added: “Students and teachers at the school are safe and all supports are in place.”