The contents uploaded to one of those account was flagged by an automatic filter as being likely malicious. And since all accounts were created from the same location, they were also suspended as a precaution.
That said, we have procedures for dealing with this. Just have your students submit a ticket for each account to have them reviewed and reactivated.
Hi there! Can you tell me who was the student that that was flagged by the malicious filter? We will have class together tomorrow and I would like to know if they will be able to continue working in your hosting service. I was also working on the same network as them and nothing happened to my account. Thanks for your support and quick answer.