The man left after a campus supervisor told him he could not remain on school grounds, according to notices both Mamaroneck and Rye Neck schools sent to parents Thursday following the late morning intrusion.
The supervisor said the man seemed to be holding a gun underneath his coat and when asked about the firearm, the man confirmed he did have one and said he worked in the security field, according to the letter.
When he was denied entry, the man said he would return later, and police were immediately notified. The Mamaroneck town police are investigating the matter.
The Rye City Schools District was made aware of the incident in Mamaroneck an hour after it happened Thursday and schools went into a high security alert at the time. All doors will remain locked to schools during the day and outdoor activities will be limited.
The Rye Police Department is aware of the incident and has been in constant communication with the district.
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