Police Commissioner Ray Kelly confirmed the delivery of the photographs to officials at Columbia's Teachers College is being actively investigated as a potential hate crime, the New York Post said Thursday.
The photograph of the noose was placed in an envelope addressed to former Columbia Professor Madonna Constantine, who was fired after a school administrative panel found her guilty of plagiarizing.
In October 2007, months before her dismissal, Constantine reported finding a noose hanging from her office door.
While the incident was investigated, no charges were ever filed in relation to the ominous delivery to the black professor's office, the Post said.
The newspaper said the other photographs in the recent university delivery were addressed to Jewish professors at Columbia and all included images of swastikas.