A school district in Mississippi asked students to bring an unopened bottle of water to school on Wednesday.

A boil water notice was issued for the Lumberton Public School District, WHLT-TV reported. The district said water fountains would not be on, according to a post on Facebook.

Bottled water will be available as needed, the district said in the post.

It’s unclear what led to the boil water notice and when it might be lifted.