A law firm’s job offer to a New York University law student was rescinded on Tuesday for what the firm described as “inflammatory comments” about Hamas’s attack that killed at least 1,200 Israelis. And at Harvard, student groups began to take back their signatures on a letter that blamed Israel for the violence.

The actions were part of a wave of fallout on campuses for students, who are deeply polarized over the fighting.

At N.Y.U., Ryna Workman, the president of the university’s Student Bar Association, wrote in a message to the group on Tuesday that “Israel bears full responsibility for this tremendous loss of life.”

“This regime of state-sanctioned violence created the conditions that made resistance necessary,” Mx. Workman wrote in the Student Bar Association bulletin. “I will not condemn Palestinian resistance.”

The backlash was swift.

By evening, the law firm, Winston & Strawn, said the comments “profoundly conflict” with its values and without naming the student, said it rescinded its offer of employment.

The same day, the dean of the law school, Troy A. McKenzie, repudiated the student’s remarks. “This message was not from N.Y.U. School of Law as an institution and does not speak for the leadership of the law school,” Mr. McKenzie wrote.

In a statement to The Times, the law school said: “For legal reasons, we cannot comment on the specifics of any current student who may be under investigation. Speaking generally, all complaints of bias and/or discriminatory behavior are investigated thoroughly and in accordance with federal, state, and local guidelines, and the appropriate disciplinary action follows the outcome of that process.”

Efforts to reach Mx. Workman were unsuccessful.

At Harvard, there was continued fallout from a letter issued over the weekend by a coalition of student groups holding Israel “entirely responsible” for the violence. On Tuesday, Bill Ackman, a prominent hedge fund manager, said that some chief executives had asked for a list of members in the student organizations, to ensure that “none of us inadvertently hire any of their members,” he wrote on X, formerly known as Twitter.

Lawrence H. Summers, a former Harvard president, had criticized the university’s administration for not immediately repudiating the student letter. But in an interview on Wednesday, he said that while he still condemned the letter, punishing individual signers would be problematic.

Some students may not have known what they were signing. “This is not a time for witch hunting or persecuting,” Dr. Summers said.

Claudine Gay, Harvard’s current president, wrote on Tuesday, “Let there be no doubt that I condemn the terrorist atrocities perpetrated by Hamas.”

Indeed, as the extent of the atrocities became clearer, some student groups retracted their signatures on Wednesday. The Harvard Undergraduate Ghungroo issued a formal apology; the Harvard Undergraduate Nepali Student Association expressed “regret,” and said that 10 Nepali students in Israel were among the civilians killed, and the Harvard Islamic Society said that it condemned “any attacks in which civilian victims pay the price.”

There were reports of a bus circulating on Harvard’s campus displaying the names and faces of students affiliated with the groups that signed the letter, prompting Harvard Hillel to condemn “any attempts to threaten and intimidate” those who signed it.

Even before the Hamas attack, the Israeli-Palestinian conflict has been one of the most contentious on campuses. In June, at the City University of New York School of Law, a student commencement speaker faced a furious backlash for denouncing “Israeli settler colonialism.” CUNY’s chancellor and board of trustees called the address “hate speech.”

At N.Y.U., the Student Bar Association voted Tuesday evening to begin the process of removing Mx. Workman as president, and it is circulating a “vote of no confidence” survey, according to a statement from the bar association.

The association said that its members apart from Mx. Workman “did not write, approve or see this message before it was published.”

As a result of the outrage surrounding the student’s message, “multiple students have received significant targeted harassment and death threats,” the group said, adding, “The doxxing of any N.Y.U. law student is unacceptable and disturbing.”

The bar association called on N.Y.U. to do more to protect students’ privacy and safety.

On Wednesday, David Tanner, the chairman of the law school’s board of trustees, and Mr. McKenzie, the dean, condemned the “terrorist attacks and the atrocities perpetrated by Hamas in Israel.”

The statement said N.Y.U. was “working 24/7 to protect the safety of all our students while providing support for those most affected by the war, here and in Israel.”

In May 2021, Mx. Workman, who is nonbinary, posted on Facebook that they were excited to be attending law school and that they wanted to help increase the number of Black female lawyers.

“As I transition into law school,” they wrote, “I want to learn how to operate as a young professional whose end goal is not to become part of the system that harms people like me and people in my community, but rather, how to become someone who breaks down those systems to help make the world we live in more equitable.”