White House press secretary Sean Spicer apologized on Tuesday for remarks that were viewed as downplaying the atrocities of the Holocaust.

In criticizing Syrian President Bashar al-Assad’s alleged use of chemical weapons during a Tuesday briefing, Spicer said that even Adolf Hitler did not sink to that level of warfare and “was not using the gas on his own people in the same way that Assad is doing,” despite Hitler’s use of gas chambers to kill millions of Jews and others.

Following hours of controversy, Spicer walked back his remarks late in the day.

“Frankly, I mistakenly used an inappropriate and insensitive reference to the Holocaust for which, frankly, there is no comparison,” Spicer said in an interview with CNN’s Wolf Blitzer on Tuesday evening that led the nightly newscasts of all three major networks. “And for that, I apologize. It was a mistake to do that.”

Blitzer, the son of Holocaust survivors, asked Spicer if he knew that the Nazis took Jews, gays, gypsies and others to death camps “to slaughter them in these poison-gas chambers.”

(Newseum)

“Yes, clearly I am aware of that,” Spicer said, adding that his original comments were meant to focus just on Assad’s use of chemical weapons dropped from aircraft. “It was a mistake to do that and, again, that’s why I should have just stayed on topic, stayed focused on the actions that Assad had taken and the horrible atrocities that he had committed against his own people.”

President Trump and his aides rarely apologize for controversial remarks or stating factual errors and often take a confrontational approach when challenged. Spicer’s decision to appear on CNN late in the day was a sign of how badly his remarks were being received both inside and outside the White House.

Spicer brought up Hitler unprompted during Tuesday’s White House briefing when asked about the alliance between Assad and Russia.

“We didn’t use chemical weapons in World War II,” Spicer said. “You had . . . someone as despicable as Hitler who didn’t even sink to the using chemical weapons.”

Later in the briefing, a reporter asked Spicer to explain what he meant.

“I think when you come to sarin gas, there was no — he was not using the gas on his own people the same way that Assad is doing,” Spicer said, mispronouncing Assad’s name.

Spicer’s comments drew stunned looks from reporters, and the mouth of one White House press aide seemed to fall open in a half gasp as he spoke. Reporters tried to correct Spicer, to remind him of the millions gassed in concentration camps, with one person shouting out: “He gassed the Jews!”

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“I understand your point, thank you,” Spicer said. “He brought them into the Holocaust center, I understand that. But what I am saying in the way that Assad used them, where he went into towns, dropped them down to innocent, into the middle of towns . . . so the use of it. And I appreciate the clarification there. That was not the intent.”

Before the briefing was even over, White House press aides realized the magnitude of Spicer’s mistake. Shortly after he stepped away from the lectern, Spicer put out a statement again trying to explain what he meant.

“In no way was I trying to lessen the horrendous nature of the Holocaust,” he said. “I was trying to draw a distinction of the tactic of using airplanes to drop chemical weapons on population centers. Any attack on innocent people is reprehensible and inexcusable.”

Social media sites lit up with outrage, concern and mockery.

Trump and several people close to him have previously faced accusations of anti-Semitism and making insensitive remarks regarding the Holocaust.

During the campaign, Trump tweeted a graphic attacking Hillary Clinton that was circulating in anti-Semitic circles online that featured a Star of David on top of piles of money. Although the image was deleted, Trump later said he wished his staff had left it in place and allowed him to defend it. In January, the White House released a statement on International Holocaust Remembrance Day that made no mention of Jews or the anti-Semitic views that fueled the Holocaust.

When confronting these accusations, Trump and those close to him note that his daughter Ivanka, son-in-law and their children are Jewish. On Monday night, the White House hosted a kosher Seder dinner for staff members. Trump did not attend but tweeted: “Happy Passover to everyone celebrating in the United States of America, Israel, and around the world. #ChagSameach.”

After the briefing, the U.S. Holocaust Memorial Museum tweeted a video showing footage taken when U.S. forces liberated a concentration camp in Germany in April 1945.

Anne Frank Center for Mutual Respect Executive Director Steven Goldstein, a frequent critic of Trump, released a statement accusing Spicer of having “engaged in Holocaust denial” and called for his firing. House Minority Leader Nancy Pelosi (D-Calif.) said Trump should fire Spicer, accusing him of “downplaying the horror of the Holocaust.”

About four hours after the briefing ended, Spicer appeared on CNN to apologize for his remarks.