President Donald Trump signed an executive order on Friday that forced six Christian refugees from Syria to return to the region they were trying to escape.

On Sunday, Trump took to Twitter defending his order as necessary to protect Christian refugees from the Middle East.

Trump’s order carves out special standing for religious minorities.

Christians in the Middle-East have been executed in large numbers. We cannot allow this horror to continue! — Donald J. Trump (@realDonaldTrump) January 29, 2017

Trump’s orders banned immigrants from seven Muslim-majority countries, which has stranded hundreds of green card holders caught en route to the United States. It also blocked refugees who arrived on visas preapproved by the US government. Thousands of people have rushed to more than 10 major airports to demand the release of these legal permanent residents.

Already there is evidence that Trump’s order is hurting, not helping, religious minorities supposedly protected by the ban. As NBC Philadelphia reported, two Christian families from Syria escaping religious persecution arrived in Philadelphia in Sunday — only to be sent back home:

The families, made of up two brothers, their wives and two children, were detained by Customs and Border Protection officials after disembarking a Qatar Airways flight at 7:25 a.m., according to Joseph Assali, of Allentown. Three hours later, the six were put back on a Qatar Airways flight to Doha, Assali said. "This is like a nightmare come true," he said, adding that they had visas and green cards legally obtained months ago. "They're all Christian citizens and the executive order was supposed to protect Christians fleeing persecution," he said.

Philadelphia Mayor Jim Kenney condemned the decision in a statement, saying Trump’s order may have given the innocent family a “death sentence.”

“They were sent back to a war-torn nation that has used chemical warfare against its own people,” Kenney said on Sunday. “The Trump administration very well may have just given these families a death sentence.”

Trump administration: We will “apologize for nothing”

Trump also held firm in the face of the uproar Sunday by pointing to “what is happening all over Europe,” an apparent reference to terrorist attacks overseas. The defiance mirrored the public statements of White House Chief of Staff Reince Priebus, who said the administration would "apologize for nothing."

Our country needs strong borders and extreme vetting, NOW. Look what is happening all over Europe and, indeed, the world - a horrible mess! — Donald J. Trump (@realDonaldTrump) January 29, 2017

Still, Trump fired off a series of tweets over the weekend blaming the media for “so false” coverage — a continuation of one of his campaign themes — and again took aim at the New York Times:

Somebody with aptitude and conviction should buy the FAKE NEWS and failing @nytimes and either run it correctly or let it fold with dignity! — Donald J. Trump (@realDonaldTrump) January 29, 2017

On Sunday, additional demonstrations are planned in at least 13 different cities to oppose Trump’s Muslim ban. One will be at the White House.

Watch: Trump’s “Muslim ban” won’t help security