Swastikas were spray-painted on two office walls of a Jewish professor at Columbia University.

The word “YID” also was spray-painted on an office wall of Elizabeth Midlarsky, a professor of psychology and education at Teachers College. Midlarsky also researches and publishes about the Holocaust.

The New York Police Department is investigating the incident, the Columbia Spectator student newspaper reported about two hours after the graffiti was discovered on Wednesday afternoon. All Teachers College academic buildings require an ID for entrance, according to the Spectator.

“I was in shock,” Midlarsky, who is 77 and says she is in poor health, told the newspaper. “I stopped for a moment because I couldn’t believe what I was seeing.”

Teachers College President Thomas Bailey said in a statement: “We unequivocally condemn any expression of hatred, which has no place in our society. We are outraged and horrified by this act of aggression and use of this vile anti-Semitic symbol against a valued member of our community.”

In 2007, Midlarsky was the victim of anti-Semitic vandalism at the university, when a swastika was spray-painted on her office door and anti-Semitic fliers were left in her mailbox.

The Anti-Defamation League in a statement issued later on Thursday offered a $5,000 reward for information leading to the arrest and conviction of the individual or individuals responsible for the vandalism.

“While we hope this reward facilitates the quick apprehension of the individual or individuals responsible for this most recent horrific incident, we all have a role to play in preventing these incidents from happening in the first instance.  We must continue to stand up and speak out against bigotry and hatred to avoid what we fear is becoming a grave and troubling normalization of hate in our region,” aid Evan R. Bernstein, regional director of ADL for New York and New Jersey.