CORRECTION: This article has been updated to reflect that, just like any day, parents may choose to call and excuse their child from school if they have a legitimate reason for doing so. Parents were given the option to excuse their child Thursday, if they felt they were unsafe.

NILES — Police at Niles High School investigated a threat Tuesday that they later ruled was not credible, according to a letter shared with parents by Niles High School Principal Molly Brawley Tuesday.

According to the letter, the threat, which read “Be ready to be scared, Nov. 1,” was displayed on a school-owned device accessible by many students.

Police determined the threat was not credible, and may be related to the Halloween season or midterm exams scheduled for that day.

“However, because of our desire to keep families informed, as well as seek assistance from the school community on all matters of safety and security, we are sending this letter home,” Brawley wrote. “Incidents like this are taken seriously and all appropriate protocols are followed, including additional precautionary measures if necessary. Niles High School staff responded immediately upon finding the message and worked directly with NCS Director of Student Services Tracy Hertsel and our school resource officer to begin an investigation. The district will enact appropriate disciplinary action, if necessary.”

The letter goes on to thank several students who brought the issue to the attention of adults in the school.

School administrators said just like any other day, parents can excuse their child for legitimate reasons on Nov. 1, according to Dan Applegate, the Niles Community School superintendent

Niles Community Schools uses OK2SAY, a confidential way to report student concerns about weapons, threats, drugs, bullying or anything else that threatens their safety. Students may call 8-55-OK2SAY (855-565-2729) or text TIPS 652729 (OK2SAY). They may also visit Michigan.gov/ok2say.