Updated

A Jewish professor found a swastika on her office door at Columbia University on Wednesday, the latest symbol of bias and hatred found at the school in recent weeks, police said.

Elizabeth Midlarsky discovered the swastika painted on her door at Teachers College, a graduate school of education affiliated with Columbia. Madonna Constantine found a noose on her office door at the college on Oct. 9. Both are professors of psychology and education.

The New York Police Department's hate crime unit is investigating both incidents. No arrests have been made, police said.

School leaders said they felt the college was being targeted because of its "deep, multicultural work."

"We are committed to maintaining that tradition by operating as an open, tolerant community," Teachers College President Susan Fuhrman and Provost Tom James said in a statement. "We will not be intimidated by these incidents."

Teachers College, founded in 1887, describes itself as the nation's oldest and largest graduate school of education.

Midlarsky's research focuses in part on altruism, and she has studied heroic rescues during the Holocaust. Her profile on the Teachers College Web site says she is working on a project on school violence.

Midlarsky did not immediately return a call seeking comment.

The discovery of the noose roiled the Ivy League campus, and students, faculty and administrators had denounced the incident targeting Constantine, who has written extensively about race.

A few days later, a caricature of a yarmulke-wearing man and a swastika were found on a university bathroom stall door. Police at the time said there was no reason to believe the two incidents were linked.

Police have said they believe one or more copycats could be responsible.

Nooses, racially charged symbols of lynchings in the Old South, have appeared in a number of recent incidents around the country.

Three white students hung nooses from a large oak tree outside a high school last year in Jena, La., fueling racial tensions. More recently, nooses have been found at the Coast Guard Academy in New London, Conn., and the Hempstead Police Department's locker room on New York's Long Island.