(CNN) — A pro-Palestinian college professor’s tenure offer at the University of Illinois was allegedly rescinded after he made anti-Israel tweets about the war in Gaza.

Dr. Steven Salaita’s case “is sort of unprecedented in a way,” said Baher Azmy, the legal director for the Center for Constitutional Rights. The organization’s legal team has advised Salaita as they consider potential legal avenues.

In October 2013, the university offered Salaita a tenured position in the American Indian Studies program, which Salaita accepted, according to Azmy. But on August 1, 2014, Salaita received a letter from Chancellor Dr. Phyllis Wise terminating the appointment.

By then, Azmy said, Salaita had resigned from his tenured position at Virginia Tech, rented his home in Virginia and was preparing to move his family to Illinois.

Virginia Tech Department Chair Joseph Eska confirmed Salaita had resigned and would not be returning in the fall.

According to University of Illinois protocol, once an offer is made, the chancellor’s office must make a recommendation to the board of trustees for final authorization. Azmy said Wise rescinded the offer before it went to the board. Azmy said he believes the reason was Salaita’s “political expressions” in social media.

Salaita’s Twitter feed includes messages like “#Israel’s message to #Obama and #Kerry: we’ll kill as many Palestinians as we want, when we want. p.s.: f— you, pay me. #Gaza”

Another post reads, “Only #Israel can murder around 300 children in the span of a few weeks and insist that it is the victim. #Gaza #GazaUnderAttack”

University spokeswoman Robin Neal Kaler said, “As a matter of university policy and practice, we do not comment publicly upon nor discuss generally any personnel matters, including matters involving employment or tenure.”

In an open letter sent to Wise, Azmy cites “viewpoint discrimination” as the reason for the dismissal, calling it a “serious First Amendment violation.”

“He resigned from a job that gave him tenure, the pinnacle of academic achievement, with the expectation that he would have tenure at the next university and it was taken away in an unlawfully retaliatory way for his political views,” Azmy said.

CNN was not able to reach Salaita but spoke to his wife, who declined to comment other than to confirm her husband had been consulting with Azmy.

CNN also was unable to reach Wise for comment. Neal Kaler did not clarify why last month she defended Salaita’s right to tweet his views during an interview with The News-Gazette, a local newspaper. She said then, “Faculty have a wide range of scholarly and political views, and we recognize the freedom of speech rights of all of our employees.”

Salaita’s controversial views were no secret at the time the university made him an offer. He is the author of six books, including “Israel’s Dead Soul” and the “Anti-Arab Racism in the USA.”

Salaita’s opinions, Azmy said, constitute the basis for his scholarly research, which was the reason he was offered the position to begin with.

Salaita believed the principles of academic freedom “would permit him to share his views without fear of censure or reprisal,” said Azmy.

Wise’s move to block the appointment has drawn criticism and support.

Cary Nelson, a longtime English professor at the university and a past president of the American Association of University Professors, supported Wise. He said, “I believe the decision not to offer him a job was the right one.”

“I find many of his tweets quite loathsome —as well as sophomoric and irresponsible,” he said, adding that “while universities need to study all positions on an issue, even the most outrageous ones, I see no good reason to offer a permanent faculty position to someone whose discourse crosses the line into anti-Semitism.”

Nelson has written on the topic of academic freedom in the past. In an essay posted on his website, he said academic freedom “is the principle that guarantees faculty members the right to speak and write as they please without interference from the university, the state, or the public.”

The Illinois Conference Committee A on Academic Freedom and Tenure of the American Association of University Professors released a statement supporting Salaita.

“Professor Salaita’s words while strident and vulgar were an impassioned plea to end the violence currently taking place in the Middle East,” the statement read. “The University of Illinois cannot cancel an appointment based upon Twitter statements that are protected speech in the United States of America.”

A Change.org petition created by an American professor of Palestinian descent in support of Salaita had garnered over 11,000 signatures.

Azmy said he had not received a response from Wise. Meanwhile Salaita’s professional future remained in limbo.

“I don’t think he knows what he is going to do,” Azmy said. “He is a scholar and scholars should be in university setting.”