KNOXVILLE, Tenn. (WATE) — Campbell County churches have been getting some strange letters. The sheriff’s office calls them “very concerning.”

The letters have been left on the front door of several local churches, a Masonic lodge and at least one business, according to the Campbell County Sheriff’s Office (CCSO).

Sheriff Robbie Goins said the letters do not have any direct threats, but the content within the letters is considered disturbing, causing his office to take them very seriously. The FBI and the Tennessee Highway Patrol are helping with the investigation.

“We don’t see any significant threat at the moment, and we want people to continue to go to church and go to their place of worship,” Goins said. “We’re working on this vigorously until we find a conclusion to it.”.

If your church or business has received one of the letters, you are asked to call the CCSO tip line at 423-562-8095. If possible, Goins said to not touch the letter to help preserve evidence.

Due to the ongoing investigation, the sheriff’s office is not providing any additional details about the contents of the letter.

The sheriff’s office is also holding a town hall event on church safety on June 23 at 6 p.m. at Jacksboro First Baptist Church.