SA schools evacuated after bomb threats

A number of Adelaide schools have been evacuated after receiving bomb threats.

Police confirmed on Thursday they were coordinating a response at the affected schools with the state education department.

The source of the threats and whether they're linked to a number of coordinated phone threats at schools across Sydney is also being investigated.

The threats were received by computer and were reportedly sent to three schools.

One of those is in the CBD with two others believed to be in the eastern suburbs.

The Department for Education and Child Development said the safety of students and staff was its top priority and it was working with police.

"The appropriate response is being made at a site-by-site level," the department said.

"Schools that have been affected will be contacting parents directly to notify them of the incident."

Hundreds of students were removed from Adelaide High School, in the CBD, after a receptionist received a phone call warning of a bomb at around 11.30am (CST).

Police confirmed the threat was a hoax and students returned to their classes about an hour later.

"You always take these things seriously, however I'm quite confident in our school and our processes to know that we can manage these things," principal Anita Zocchi told reporters.