Seattle public schools will close tomorrow and remain closed “for a minimum of 14 days,” according to a notice from the district to parents.

In a letter to students’ families, the district says, “Together, we are facing an unprecedented health crisis in our community.” The notice does not say if they will attempt to continue instruction remotely, although the district promises to have more details for parents on Thursday.

The school district says its first staff member tested positive for the novel coronavirus Tuesday, but they expect the number of cases tied to the district to increase.