Protestors rally at John F. Kennedy International Airport on Saturday in New York City. President Trump signed an executive order that enacted a 90-day ban on refugees and immigrants from certain predominantly Muslim countries. (Stephanie Keith/Getty Images)

U.S. colleges and universities are rushing to help students and scholars affected by President Trump’s order restricting all citizens from seven Muslim-majority nations from entering the United States, and academic leaders are warning that the executive action could cause irreparable harm to American higher education.

Trump’s order bars immigrants from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen for 90 days and indefinitely keeps out Syrian refugees. A few federal judges put some limits on the executive order late Saturday but the overall thrust of it remained intact.

School officials urged students and scholars in the United States who may be affected by the decree not to travel internationally for any reason as stories emerged about some now stranded overseas, unable to return to their schools or start planned study and research.

At least 21 Nobel laureates and numerous academics signed a petition against the executive order. The Association of American Universities issued a statement by its president, Mary Sue Coleman, saying in part:

[T]he Administration’s new order barring the entry or return of individuals from certain countries is already causing damage and should end as quickly as possible. The order is stranding students who have been approved to study here and are trying to get back to campus, and threatens to disrupt the education and research of many others. We also urge the Administration, as soon as possible, to make clear to the world that the United States continues to welcome the most talented individuals from all countries to study, teach, and carry out research and scholarship at our universities. It is vital to our economy and the national interest that we continue to attract the best students, scientists, engineers, and scholars. That is why we have worked closely with previous administrations, especially in the wake of 9/11, to ensure our visa system prevents entry by those who wish to harm us, while maintaining the inflow of talent that has contributed so much to our nation. Other countries have set the goal of surpassing the United States as the global leader in higher education, research, and innovation. Allowing them to replace this country as the prime destination for the most talented students and researchers would cause irreparable damage, and help them to achieve their goal of global leadership.

Stanford University President Marc Tessier-Lavigne and other officials also issued a message for their school community, providing information about the executive order and expressing concern about one student in particular.

We are quite concerned about the experience of one of our students upon returning to the United States from Sudan late Friday. This graduate student, a legal permanent resident of the United States, was detained for several hours at Kennedy International Airport, and handcuffed briefly, upon trying to return from a research trip. While thankfully she was released, we are enormously concerned about the anguish this episode caused our student and her family, and what it may suggest for others in similar situations. An unfortunate consequence of the new policy appears to be that students and scholars from designated countries are, for the moment, effectively detainees in this country.

MIT officials issued a statement Saturday saying they were “very troubled by this situation” and “are working closely with them to offer every support we can.” The University of Michigan at Ann Arbor issued a statement Saturday night that says in part:

The leadership of the university is committed to protecting the rights and opportunities currently available to all members of our academic community, and to do whatever is possible within the law to continue to identify, recruit, support and retain academic talent, at all levels, from around the world.

The Harvard Crimson, the student newspaper, reported that at least two Iranian scholars scheduled to come to Harvard Medical School to study and conduct research were barred from coming to the United States by Trump’s action. Seyed S. S. Saravi is a scientist who had been awarded a fellowship to study cardiovascular medicine. Samira Asgari had planned to do research on tuberculosis.

Yale University leaders, including President Peter Salovey, sent a community-wide message saying that they are “working closely with students and scholars who are directly affected.”

Ángel Cabrera, president of George Mason University in Virginia, posted this tweet: