Police are investigating an incident Monday involving a letter of hate and noose sent to a high school principal.

Police say the principal at Canarsie High School received the letter and the noose through the mail. Staff and students at the school say they were unaware of what happened to the principal.

The discovery is among a number of recent incidents, locally andnationally, involving the symbols of lynchings in the Old South.

Nooses were found earlier this month on a black professor's doorat Columbia University, outside a post office near ground zero inManhattan and in four locations on Long Island. There have been noarrests in any of those cases.

AP wires contributed to this story