A bomb threat was reported at Pontiac High School and students were evacuated as a result, police say.
The school liaison officer assigned to the school received information from a teacher that a student had found a note inside a classroom that stated "I HAVE A MOMB #L.D.G."
Police say it is unknown who left the note or how long the note had been there.
Students and teaching staff were evacuated onto the football field while Oakland County Sheriff's deputies and a bomb detection K-9 Unit conducted a search for any explosive device.
Police say nothing suspicious was located.
Students were dismissed at their normal dismissal time and staff members were allowed to return to the school. The note was turned over to detectives, who are continuing with the investigation.