Harvard University President Claudine Gay responded to criticism by students and alumni including Bill Ackman that the school isn’t doing enough to protect Jewish students, saying it would expand its diversity program to combat antisemitism.

The Ivy League university has come under intense criticism that started the day of the Oct. 7 Hamas attack on Israel. More than 30 student groups issued a statement that blamed Israel for the attack and not Hamas, which is classified as a terrorist group by the U.S. and European Union.

Since then, protests at Harvard by pro-Palestinian groups have included intimidation, online messages and shouts of “From the River to the Sea, Palestine Shall Be Free,” Ackman said. In a letter to Gay posted on X over the weekend, the hedge fund manager described the situation on the Cambridge, Massachusetts, campus as “dire” after meeting with students and faculty.

“Our community must understand that phrases such as ‘from the river to the sea’ bear specific historical meanings that to a great many people imply the eradication of Jews from Israel and engender both pain and existential fears within our Jewish community,” Gay said in an email to the Harvard community Thursday. “I condemn this phrase and any similarly hurtful phrases.”

Harvard has heard from furious alumni who have threatened to stop donating — from billionaires like Ackman to dozens of alumni who have pledged $1 and condemned Harvard’s failure to address the campus culture. In response, Gay has issued multiple letters denouncing antisemitism, formed an advisory group and planned to create training for students, faculty and staff on antisemitism broadly and at Harvard specifically. She attended a Hillel dinner and posted comments on her web page.

In her latest message, Gay also addressed an incident on the Harvard Business School campus on Oct. 18 that is being investigated by the FBI and the Harvard University Police Department. Videos circulated online show what appears to be Harvard students harassing a Jewish student during an anti-Israel protest.

“Consistent with our standard practice, once law enforcement’s inquiry is complete, the University will address the incident through its student disciplinary procedures to determine if University policies or codes of conduct have been violated and, if so, take appropriate action,” Gay wrote.

Ackman had asked for immediate responses, and in a post Friday, slammed Harvard and the Massachusetts Institute of Technology for failing to discipline protesters who violate their rules, further emboldening those to more “aggressive, disruptive and antisemitic actions.”

‘This has created a climate of fear that is not conducive to a university education,” Ackman wrote on X. “The failure to discipline students who have bullied, assaulted or otherwise been abusive to Jewish students under the guise of free speech or a supposed requirement to wait for the completion of a police and FBI investigation is similarly absurd.”

Ackman included a post from Massachusetts Institute of Technology Professor Retsef Levi who wrote of continued harassment on his campus, including protests supporting Hamas, despite the administration setting guidelines to avoid “unsafe protests on campus.”