A threatening note left on the doors of John Essex School on Monday allegedly saying students should be out of the school by Friday has law enforcement officials and school officials preparing for the school day on Friday.

“We worked closely with the Marengo County Sheriff’s Department as far as monitoring the school day and night,” said Marengo County Schools superintendent Luke Hallmark. “There will be security there (on Friday) probably before the students even get there. They’ll be around the school, and they’ll be there tonight (Thursday) to make sure that everything is going OK.”

Marengo County officials closed John Essex School for all day on Monday after school officials discovered a bomb threat taped to the school’s doors before the school day began.

Students who were already at the school were evacuated to the school’s football field, and parents came in to pick up their children.

A search of the building by Marengo County Sheriff’s Department personnel and bomb-sniffing dogs brought down from Tuscaloosa found no evidence of any explosives on the campus. The students returned to school on Tuesday, and will make up the lost day on Tuesday, Feb. 17, originally scheduled as an in-service day.

Marengo County Sheriff Jesse Langley said the incident is under investigation.