The professor, Elizabeth Midlarsky, a clinical psychologist who has done studies on the Holocaust, said the college’s associate provost called to notify her of the swastika. Ms. Midlarsky said it was actually the third time in recent weeks that she had been the target of bias.

On Oct. 17, she said, she found an anti-Semitic flier in her mailbox at work. She said she found two more copies of the same flier in her mailbox on Oct. 24. She said she reported those incidents to Columbia officials.

“I see this as an attack of extreme hate and extreme cowardice by someone trying to make a point,” Dr. Midlarsky said yesterday. The police said they had no suspects.

On Oct. 10, a noose was found on the office door of Madonna G. Constantine, a black professor at the college. A string of similar acts in the region have occurred in recent weeks, including one in which a Brooklyn principal received a noose along with a racially charged letter in the mail.