Lawrence Summers, the former president of Harvard University, said he was “sickened” by the institution’s lack of response after some student groups blamed Israel for Hamas’ attack, which has killed more than 900 Israelis, most of them civilians.

“The silence from Harvard’s leadership, so far, coupled with a vocal and widely reported student groups’ statement blaming Israel solely, has allowed Harvard to appear at best neutral towards acts of terror against the Jewish state of Israel,” Summers said on X, formerly known as Twitter.

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Summers, who resigned as president of Harvard in 2006 after clashing with faculty, including over remarks he made about women’s aptitude for science and engineering, said that in almost 50 years of affiliation with Harvard, he’s never been as “disillusioned and alienated as I am today.”

After Summers’ posts, Harvard released a statement late on Monday titled “War in the Middle East” signed by university leaders, including president Claudine Gay.

The statement spoke of the “death and destruction unleashed by the attack by Hamas that targeted citizens in Israel this weekend, and by the war in Israel and Gaza now under way.”

The former US Treasury Secretary and Harvard President Emeritus had contrasted the university’s initial reaction to the approach taken in the aftermath of Russia’s invasion of Ukraine — after which it flew the Ukraine flag in solidarity — and when Gay, at the time Dean, wrote powerfully about the killing of George Floyd in 2020.

More than 30 student groups signed a “Joint Statement by Harvard Palestine Solidarity Groups on the Situation in Palestine,” which said it held the Israeli regime “entirely responsible for all the unfolding violence” and that the Hamas attack didn’t “occur in a vacuum.”

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Summers, a Harvard University professor and paid contributor to Bloomberg TV, said there’s nothing wrong with criticism of Israeli policy, but that’s “very different from lack of clarity regarding terrorism.”

Harvard declined to comment on Summers’ social media post.

--With assistance from Janet Lorin.

(Updates with Harvard statement in fourth paragraph.)