A professor at Columbia University Teachers College found a noose hanging outside of her office door yesterday morning, police officials said.

Police said the unit’s detectives are investigating the incident.

Police did not release the name of the professor, who they said is black and 44-years-old. The president of Teachers College, Susan Fuhrman, sent a notice to students, faculty, and staff yesterday, saying she deplores “this hateful act, which violates every Teachers College and societal norm,” according to a spokesman, Joe Levine.

“I can’t speculate who did it, I have no idea,” Mr. Levine said, noting the building’s doors are locked and guarded by security officers. He said the college would organize community gatherings to deal with the incident.

There were six bias incidents on Columbia’s campus in the 2005-06 school year, according to news reports. In one incident, two students were arrested for drawing swastikas and homophobic slurs in the hallway of a dormitory.

In 2004 there were three bias incidents that included a racist cartoon mocking Black History Month and a bake sale against affirmative action, a news report said. A campus “Stop Hate” coalition rallied in response to those incidents.

Most recently, a visit from President Ahmadinejad of Iran prompted large protests. Mr. Ahmadinejad denied that homosexuals exist in Iran during his speech at Columbia.

The most recent incident comes on the heels of a racial conflict in Jena, Louisiana in which white high school students hung a noose from a tree to intimidate black students.