EDEN VALLEY — A central Minnesota school district was under lockdown Wednesday after a possible threat was posted on Facebook.

Eden Valley-Watkins Superintendent Larry Peterson tells KMSP-TV the high school principal saw the possible threat posted on the school’s page sometime late Tuesday or early Wednesday. The post said “I see dead people” and had a picture of the school attached.

As a precaution, the district’s three schools were ordered into lockdown for the school day. Visitor access was strictly limited, and students, faculty and staff were kept in their schools until the normal end of their day.

Schools in the district include Eden Valley Elementary, Watkins Elementary and the Eden Valley-Watkins secondary school.

The Meeker County sheriff’s office says students were released for the day without any incidents. The investigation continues.