Kalamazoo Public Schools has been without internet and email access since Wednesday following a network security incident.
The district, known as KPS, said it does not believe the incident was a targeted attack.
A third-party information technology firm is investigating the cause of the issue and assessing its scope.
Officials have not provided specific details about the nature of the security incident.
The district remains offline as of Friday, May 2, stating it will not reconnect until it is safe to do so.
Despite the lack of internet access and email, classes are still being held. Middle school conferences were canceled this week because of the situation.
The district's phone system is not impacted by the security event.
In a statement, KPS outlined its response.
“Our goals right now are to fully investigate the cause and restore full functionality as quickly and safely as possible,” KPS wrote in a letter sent to employees and families.
The district added, "To protect the integrity of the ongoing investigation, we are unable to share additional information about the nature of the incident at this time."