Police say they are investigating a written threat that was discovered inside a Rockland County middle school.

According to investigators, a student found the graffiti at Haviland Middle School in the Town of Hyde Park on Thursday.

Police say that student alerted school personnel, who brought it to the attention of administration.

According to authorities, photographs were taken of the writing before district janitorial staff removed it. The substance of the threat and where it was written was not immediately known.

Officers responded to the school around 4:45 p.m. Police say they interviewed those aware of the writing and reviewed surveillance footage.

Investigators say they are still working to identify the person responsible for the threat.

The incident comes just over a month after an armed man in tactical gear was spotted riding a bicycle through a field behind the middle school. Daniel Prospero, 54, was later arrested in connection with this incident.

Police ask anyone with information about the written threat to call the Town of Hyde Park Police Department at 845-229-9340 and ask to speak with Officer Passantino or Detective Felicello.