“We support liberation by any means necessary, including armed resistance,” the group, Columbia University Apartheid Divest, said in its statement revoking the apology. The group marked the anniversary of the Oct. 7 attack on Israel by distributing a newspaper with a headline that used Hamas’s name for it: “One Year Since Al-Aqsa Flood, Revolution Until Victory” it read, over a picture of Hamas fighters breaching the security fence to Israel. And in an essay, it called the Oct. 7 attack a “moral, military and political victory,” and quoted Ismail Haniyeh, the assassinated former political leader of Hamas.

“The Palestinian resistance is moving their struggle to a new phase of escalation and it is our duty to meet them there,” the group wrote on Oct. 7 on Telegram. “It is our duty to fight for our freedom!” The group’s increasingly radical statements are being mirrored by pro-Palestinian groups on other college campuses, including in a series of social media posts this week that praised the Oct. 7 attack. They also reflect the influence of more extreme protest groups off campus, like Within Our Lifetime, that support violent attacks against Israel.

“Long live October 7th,” Nerdeen Kiswani, the head of Within Our Lifetime, wrote on X on Tuesday.

Image Nerdeen Kiswani, the founder of Within Our Lifetime, holds up her arms in the middle of a crowd of protesters, many wearing kaffiyehs.

Within Our Lifetime, a group founded by Nerdeen Kiswani, center, supports violent attacks against Israel. It is increasingly influential on campuses.Credit...Adam Gray for The New York Times

The rhetoric poses a challenge to university administrators who must decide how to handle students and student groups that take such positions. Their statements are broadly protected under the First Amendment but could lead to federal investigations into campus antisemitism or on campus discipline if they are deemed to create a hostile environment for Jewish students.

“Statements advocating for violence or harm are antithetical to the core principles upon which this institution was founded,” said Ben Chang, a spokesman for Columbia.

Oren Segal, vice president of the A.D.L. Center on Extremism, said that there were chants and other messages “filled with support for terrorist organizations” at many of the over 100 protests the organization tracked on and off campuses around the country marking the anniversary of Oct. 7.

“I mean, literally, there were images of paragliders,” he said, and added, “There were multiple chants of glory to the resistance.”

The Oct. 7 attack on Israel by Hamas killed about 1,200 people, according to Israeli authorities, and about 250 hostages were taken. Many hostages have died or been killed. Since the start of the war, more than 40,000 people in Gaza have been killed, according to local health officials. The majority of the people were civilians, and hundreds of thousands more have faced starvation.

Some students who have sympathy for pro-Palestinian student actions last semester disagree with the hard-line turn in the movement. In interviews at Columbia and Barnard last week, several students said that between student activists’ harsher stances, and the threats of punishment from administrators for participating in protests, their desire to protest has lessened.

“I think this whole situation and the way that it’s been handled on my campus has absolutely no eye for nuance,” said Bellajeet Sahota, a Barnard senior, who added she was “a little meek when it comes to campus protests.”

“I also think my fellow students, as much as I love them, also have no eye for nuance,” she said.

Students for Justice in Palestine, a pro-Palestinian student group that has chapters at hundreds of colleges across the country, was among the groups whose members posted praise for the Oct. 7 attack. “Al-Aqsa Flood was a historic act of resistance against decades of occupation, apartheid, and settler colonial violence,” the Brown chapter of Students for Justice in Palestine posted on Instagram.

The increasingly revolutionary tilt of the student movement reflects an internal push among many pro-Palestinian groups to align their goals with principles known as the Thawabet, crafted by the Palestine Liberation Organization in 1977. They include the right of Palestinians to armed resistance and to self-determination on all the land from the Jordan River to the Mediterranean Sea.

In a series of posts on Substack, Columbia University Apartheid Divest, or CUAD, narrated its own evolution since last semester from an organization that saw itself in April as a “continuation of the Vietnam antiwar movement” focused on pushing Columbia to divest from Israel to one that now openly backs armed resistance by Hamas and other groups.

Citing revolutionary thinkers, like Vladimir Lenin and Frantz Fanon, it explained how solidarity was essential with members of the so-called Axis of Resistance — which includes Iran, Hezbollah, the Houthis and Hamas — because they oppose imperialism.

Since then, the group has praised a Tel Aviv attack by Palestinian militants that killed seven people at a light rail station on Oct. 1, including a mother who died while shielding her 9-month-old baby. It also praised Iran’s missile attack on the Jewish state that began that evening, calling it a “bold move.”

On Tuesday, the group said it rescinded an apology it made last spring about the behavior of Khymani James, a student who had said in a disciplinary hearing that “Zionists don’t deserve to live,” and, “Be grateful that I’m not just going out and murdering Zionists.”

“We let you down,” the group wrote in a statement, referring to Mr. James. No longer, the group vowed, would it “pander to liberal media to make the movement for liberation palatable.”

Mr. James, who is suing Columbia over his ongoing suspension, thanked the group. “I will not allow anyone to shame me for my politics,” he wrote on social media. “Anything I said, I meant it.”

Students for Justice in Palestine and Jewish Voice for Peace remain suspended at Columbia, but are active on social media. Some of their members organize through CUAD, which is not an officially recognized student group.