Hackers demand ransom from Portland area school district May 06 2021 Centennial School District confirmed a recent computer attack was ransomware and said its computers are still offline. Centennial School District confirmed Wednesday, May 5, that the attack on its computers was ransomware and although its computers are still offline, it expects students will be back to online learning by May 14. The school district announced Monday, April 26 that it "discovered that certain files on its systems were encrypted by an unknown actor." In a ransomware attack, hackers disable computer systems and then demand payment to make the computers work again. "The District can now confirm that the file encryption that it observed was the result of a ransomware attack by sophisticated cyber criminals," the district said in a statement on Wednesday.