KENT, Ohio (WJW) — Kent schools were locked down Friday afternoon after an unknown caller threatened to bring an AK-47 to the elementary school.

An unknown male called Walls Elementary School at about 2 p.m., according to a news release from the Kent Police Department, prompting “precautionary safety measures” at Walls and two other schools.

“The Kent Police Department, with the help of the Kent State University Police Department, provided for the safety of all students, faculty, and staff at these three school buildings while they completed dismissal,” reads the release.

The incident is under investigation.