A Stanford University instructor has been removed from the classroom amid reports they called Jewish students colonizers and downplayed the Holocaust

An instructor at Stanford University has been removed from teaching duties as the school investigates reports that during a discussion on the conflict between Israel and Hamas, the instructor downplayed the Holocaust and singled out students “based on their backgrounds and identities.”

“Without prejudging the matter, this report is a cause for serious concern. Academic freedom does not permit the identity-based targeting of students,” Stanford said in a statement Wednesday.

“The instructor in this course is not currently teaching while the university works to ascertain the facts of the situation,” the statement continued.

The instructor, who is not a faculty member, has not been named. CNN has reached out to the instructor for comment.

The university’s action comes as fierce fighting this week between Israel and Hamas militants in Gaza has increased tensions beyond the Middle East.

Some Jewish people in the US say they fear being targeted as the country contends with widespread reports of antisemitism. Last year, the Anti-Defamation League, which tracks antisemitic incidents, recorded nearly 3,700 incidents in the US, the highest amount since tracking began in 1979.

Rabbi Dov Greenberg, executive director of Rohr Chabad House, Stanford’s Jewish community center, told CNN the students were “shaken up.”

Greenberg, who said he spoke with the students involved in the incident, said they are “not doing well” and are afraid to face backlash or bullying on campus.

According to Greenberg, the students said the instructor tried to justify the actions of Hamas and asked the students how many Jews were killed in the Holocaust.

After one student answered “6 million,” the instructor then said more people have been killed by colonizers and said, “Israel is a colonizer.”

The instructor then illustrated his point by asking some students to physically go to the back of class. “That’s what Israel does to Palestinians,” the teacher said, according to Greenberg.

“That was the main exchange that made students feel marginalized, attacked, and isolated,” said Greenberg.

The students who spoke to Greenberg did not push back against the instructor at the time. “The students told me clearly they were traumatized, frightened. They could not believe this was happening to them,” Greenberg said.

“This is a classic case of young students, first time away from home, feeling traumatized,” Greenberg said of the college freshmen. “They did not feel like they had the capacity at this time to argue with a teacher at Stanford. They’re just kids.”

The Stanford instructor’s alleged comments came during two classes Tuesday, with a total of 18 students, during which the instructor announced the day’s lesson would focus on colonialism, the San Francisco Chronicle reported. The outlet cited Jewish student leaders who spoke with students in the course called College 101, a required class for first-year students.

Nourya Cohen and Andrei Mandelshtam, co-presidents of the Stanford Israel Association, said the students told them the instructor asked Jewish students to raise their hands, separated those students from their belongings and said they were simulating what Jews were doing to Palestinians, the Chronicle reported.

The students with whom Cohen and Mandelshtam spoke asked to remain anonymous, the Chronicle said.

Cohen and Mandelshtam declined CNN’s request for comment.

Students told Cohen and Mandelshtam the instructor brought up the colonization of Congo by Belgium’s King Leopold II in the 19th century and said more people were killed then than during the Holocaust, and Israel had colonized Palestinians, the Chronicle reported.

Students from both classes told Cohen and Mandelshtam the instructor asked students where their ancestors were from and labeled them as a “colonizer” or “colonized,” according to the Chronicle.

“I feel absolutely dehumanized that someone in charge of students and developing minds could possibly try and justify the massacre of my people,” Cohen told the newspaper. “It’s like I’m reliving the justification of Nazis 80 years ago on today’s college campus.”

The instructor’s reported comments come months after Stanford’s campus police department opened a hate crime investigation into an antisemitic drawing discovered on a whiteboard attached to a Jewish student’s dorm room door.

And in February, multiple swastikas, the N-word and the letters “KKK” were scratched into a metal panel in a bathroom on campus, the university said.

“We have heard many expressions of concern regarding student safety. We have heard from Jewish students, faculty, and staff concerned about rising antisemitism. We have heard from Palestinian students who have received threatening emails and phone calls,” Stanford said in its Wednesday statement. “We want to make clear that Stanford stands unequivocally against hatred on the basis of religion, race, ethnicity, national origin, and other categories.”

CNN’s Rebekah Riess contributed to this report.

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