Teachers desperately scrambling to prepare for online classes next week have been dealt another blow, with a cyber attack on the NSW Department of Education leaving them unable to access vital materials and tools.
The department confirmed on Thursday it had been the victim of a cyber attack.
The department deactivated a number of internal systems as a precaution on Wednesday. They were still not available on Thursday afternoon.
"This is having an incredible impact on teachers and principals," NSW Teachers Federation president Angelo Gavrielatos told AAP.
"It means that they cannot access any information, not even the guidelines for operation next week, they can't access their emails, can't access their calendars, can't access teaching materials, can't access Zoom."
The attack came just hours after Premier Gladys Berejiklian announced on Wednesday that schools in Greater Sydney would move to online learning for the first week of Term 3, which starts next Tuesday.
Department Secretary Georgina Harrisson acknowledged on Thursday that the attack "creates considerable challenge" for staff preparing for next term.
Ms Harrisson said she was confident all systems would be back online before Tuesday. In the meantime, the department is putting information to support home learning on its website to aid teachers' preparations.
Cyber Security NSW has been called in to work on the issue, and the matter has been referred to the NSW Police and federal agencies as well.
Ms Harrisson said the decision to take some systems offline while investigations are underway was made to protect the safety and security of student and staff data.
Mr Gavrielatos said the attack left school staff in "a state of paralysis".
"This has made preparation for next week impossible," he said. "It's causing incredible stress across the teaching service."
Education Minister Sarah Mitchell tweeted on Thursday afternoon: "I understand many teachers will be angry about the situation but please know everything is being done to reactivate as soon as possible."