The Anti-Defamation League (ADL) on Friday voiced concern over recent comments made by the three top Republican presidential candidates about Muslim refugees in the aftermath of the deadly terror attacks in Paris.

On Thursday, Republican presidential frontrunner Donald Trump expressed support for the creation of a mandatory database to track Muslims in the United States if he were elected president. “I would certainly implement that. Absolutely,” Trump told NBC News during a press conference ahead of a campaign stop in Newton, Iowa on Thursday. “There should be a lot of systems, beyond databases. We should have a lot of systems.”

Trump’s spokeswoman Katrina Pierson said in an interview on Fox Business News, Friday morning, that Trump “is just saying he won’t rule anything out.”

“Those are a reporters’ words, and now everyone is saying it’s all Trump. He’s simply saying he won’t take anything off the table,” Pierson said.

The comments drew rebukes by Republicans and Democrats alike.

Democratic presidential candidate Bernie Sanders issued a short statement, saying, “This is an outrageous and bigoted statement. Mr. Trump should be ashamed of himself. We will not destroy ISIS by undermining the Constitution and our religious freedoms.”

“This is shocking rhetoric. It should be denounced by all seeking to lead this country,” Hillary Clinton tweeted. Although, she has yet to denounce similar comments made by her supporter Haim Saban.

Jeb Bush and John Kasich also criticized Trump.

“That’s just wrong,” Bush said on CNBC on Friday. “It’s manipulating people’s angst and their fears. That’s not strength. That’s weakness.”

Kasich, whose Super PAC is launching a $2.5 million ad buy of negative ads against Trump in NH, said Trump is proving he’s not suited to serve as president. “The idea that someone would have to register with the federal government because of their religion strikes against all that we have believed in our nation’s history,” Kasich said in a statement. “It is yet another example of trying to divide people, one against the other. Donald Trump is unable to unite and lead our country.”

But probably the harshest comments came from a non-partisan group aimed at fighting bigotry and hatred.

“Donald Trump’s suggestion that we use a database to track Muslims is deeply troubling and reminiscent of darker days in American history when others were singled out for scapegoating,” the ADL said in a statement. “No American should be singled-out by security officials on the basis of immutable characteristics, such as religion. Such a proposal is not only inimical to our cherished civil liberties but it also wildly misses the goal of finding a rational balance between civil liberties and the security measures necessary to protect those liberties.”

The Jewish group also voiced concern at recent comments by Senator Ted Cruz proposing that the country admits only Christian refugees, as well as remarks by Ben Carson comparing Syrian refugees to ‘rabid dogs.’

Jeb Bush also suggested admitting Syrian Christians instead of Muslims. “At a minimum we ought to be bringing in people that have — orphans or people that clearly aren’t going to be terrorists. Or Christians,” Bush said in South Carolina. “There are no Christian terrorists in the Middle East; they’re persecuted.”

But the ADL, explicitly, denounced Carson and Cruz, probably since they are running 2nd and 3rd to Trump in recent national polls. “It is also regrettable that some prominent candidates, including Ted Cruz and Ben Carson, have also made remarks crossing the line into scapegoating Syrian refugees. When leading presidential candidates compare Syrian refugees to “rabid dogs,” or call for the creation of a database of Muslims, or recommend a ban on all Muslims entering the United States, they are playing to our basest instincts,” the ADL said. “We are better as a nation than what we have shown, and today we call on Americans to reject hatemongering and xenophobia. What we have been hearing is unacceptable. Yes, we can and must protect ourselves, but we must do so without sacrificing our fundamental principles of freedom and liberty.”