Republican Donald Trump lashed out Saturday at two Muslim American parents who lost their son while he served in the U.S. military in Iraq and who appeared at the Democratic National Convention last week, stirring outrage among critics who said the episode proves that Trump lacks the compassion and temperament to be president.

Asked to comment on the convention speech of Khizr Khan, a Pakistani immigrant whose son, Army Capt. Humayun Khan, died in Iraq in 2004, Trump described Khan as “very emotional” and said he “probably looked like a nice guy to me” — then accused him of being controlled by the Clinton campaign.

“Who wrote that? Did Hillary’s scriptwriters write it?” he asked in an interview with ABC.

Trump also questioned why Khan’s wife, Ghazala, did not speak on stage, despite the fact that she sat for an interview with MSNBC the following day.

“His wife, if you look at his wife, she was standing there. She had nothing to say. She probably, maybe she wasn’t allowed to have anything to say,” he said. “You tell me, but plenty of people have written that. She was extremely quiet and it looked like she had nothing to say.”

Muslim American Khizr Khan, whose son Humayun was killed while serving in the U.S. Army, offered Republican candidate Donald Trump his copy of the Constitution during a speech at the Democratic convention. (The Washington Post)

The Khans appeared in Philadelphia on Thursday, the same night that Trump’s Democratic opponent, Hillary Clinton, formally accepted her party’s nomination. Khizr Khan’s moving remarks quickly reverberated beyond the arena, and their effects have since spilled out onto the campaign trail. In an interview the following day with MSNBC, Ghazala Khan said she did not speak because she is still devastated by her son’s death and grows emotional when she sees his picture.

Although only the latest instance in which Trump has attacked a convention speaker, the Republican nominee’s remarks drew strong rebukes Saturday — but only silence from several senior GOP leaders, including House Speaker Paul D. Ryan, Senate Majority Leader Mitch McConnell and the vice-presidential nominee, Indiana Gov. Mike Pence.

“Trump’s slur against Captain Khan’s mother is, even for him, beyond the pale,” tweeted John Weaver, a Republican strategist for Ohio Gov. John Kasich. “He has NO redeeming qualities.”

Matt Mackowiak, another GOP strategist, tweeted: “There is only one response for Trump to the criticism: ‘As an American, I deeply appreciate the patriotic sacrifice of the Khan family.’”

The Clinton campaign’s Karen Finney offered this: “Trump is truly shameless to attack the family of an American hero. Many thanks to the Khan family for your sacrifice, we stand with you.”

In Youngstown, Ohio, on Saturday, Clinton addressed the controversy as part of a larger discussion of Trump’s temperament.

“He attacked the distinguished father of a soldier who had sacrificed himself for his unit, Captain Khan,” Clinton said in disbelief.

In a statement earlier that day, she said: “I was very moved to see Ghazala Khan stand bravely and with dignity in support of her son on Thursday night. And I was very moved to hear her speak last night, bravely and with dignity, about her son’s life and the ultimate sacrifice he made for his country.”

With Ghazala by his side on the convention stage last week, Khizr Khan blasted Trump’s rhetoric on Muslims and immigrants. Pulling his pocket version of the Constitution from his jacket, he questioned whether Trump has read the document.

“You have sacrificed nothing and no one,” Khan said in a halting and forceful voice.

In the ABC interview, Trump pointed to the sacrifices he has made as a businessman: “I think I’ve made a lot of sacrifices. I work very, very hard. I’ve created thousands and thousands of jobs, tens of thousands of jobs,” Trump said.

“I think my popularity with the vets is through the roof,” he added later.

The backlash was swift and unsparing Saturday as high-profile political strategists from both parties tore into Trump and questioned his character.

“Trump revealed exactly who he is in this answer and it’s not pretty. A man this callous and cruel can’t be President,” former Obama senior advisor Dan Pfieffer fired off on Twitter Saturday afternoon.

“There is still a role for shame in society,” Stuart Stevens, former top strategist to 2012 GOP nominee Mitt Romney, tweeted out Saturday in response.

Paul Rieckoff, the founder and chief executive of Iraq and Afghanistan Veterans of America, told ABC that Trump’s comparison of his own sacrifice to that of war veterans is an insult.

“For anyone to compare their ‘sacrifice’ to a Gold Star family member is insulting, foolish and ignorant. Especially someone who has never served himself and has no children serving,” he said. “Our country has been at war for a decade and a half, and the truth is most Americans have sacrificed nothing. Most of them are smart and grounded enough to admit it.”

In a statement titled “Setting the Record Straight,” Trump called Humayun Khan a “hero” but rejected his father’s accusations.

“While I feel deeply for the loss of his son, Mr. Khan who has never met me, has no right to stand in front of millions of people and claim I have never read the Constitution, (which is false) and say many other inaccurate things,” the statement read. “If I become President, I will make America safe again.”

Trump avoided the draft during the Vietnam War through several student deferments. He was later medically disqualified from service.

Several of Trump’s critics said Saturday that Trump’s attacks on the Khans are part of a broader pattern in which the candidate lashes out at others in extraordinarily personal terms for criticizing him. Many say that voters should worry about what it means in terms of Trump’s temperament and, in particular, how he would deal with foreign leaders as president.

“He’s a person that has no self-control. He just has no sense of decency or empathy when it comes to dealing with others,” said Tim Miller, a veteran GOP strategist and former communications director for Jeb Bush. “It’s always zero sum. You compliment me, I compliment you. You criticize me, I mock you. That’s what this is about. It’s all about him and his egotism.”

Miller added that Trump’s past statements, including his attack against Sen. John McCain (R-Ariz.) for being a prisoner of war, have given Democrats an opening to defend the service of veterans in direct response to the Republican nominee’s own words.

Humayun Khan had completed four years of service before he was sent to Iraq. He was killed four months after he arrived.

To cope with their grief in the aftermath of his death, the Khans moved to Charlottesville in order to be closer to their two other sons, who were attending the University of Virginia, as Humayun had. The Khans have also described at times attending funerals for other soldiers at Arlington National Cemetery as a way of remembering their son.

In the MSNBC interview, Ghazala Khan explained why she did not speak Thursday: “I was very nervous because I cannot see my son’s picture, and I cannot even come in the room where his pictures are. And that’s why. I saw the picture [behind] my back, I couldn’t take it and I controlled myself at that time.”

On Saturday, her husband criticized Trump’s response. “That is typical of a person without a soul, without empathy,” Khizr Khan said in Washington. “And Ghazala… she was in such a shape. She was emotionally and physically, she just couldn’t even stand there, and when we left, as soon as we got off camera, she just broke down. And the people inside, the staff, were holding her, consoling her, and she was just totally emotionally spent. And only those parents that have lost their son or daughter could imagine the pain that such memory causes.”

Trump’s comments about the Khan family are the latest in a series of searing attacks against individuals who spoke at the Democratic convention, including retired four-star Marine Corps Gen. John Allen, whom Trump referred to as a “failed general” during a campaign event in Denver Friday evening.

On the second day of a bus tour through Pennsylvania and Ohio with running mate Sen. Tim Kaine, Clinton continued to build a damaging portrait of the real estate mogul, an extension of the dominant theme at the convention last week to paint the Republican nominee as a self-interested and dangerous “con.”

“He loses his cool at the slightest provocation,” Clinton said of Trump in Johnstown, Pa. “Just yesterday, he went after retired general John Allen, who commanded our troops in Afghanistan. Gen. Allen is a distinguished Marine, a hero and a patriot. Donald Trump called him a failed general. Why? Because he does not believe Donald Trump should be commander in chief.

“Well, I’d say that proves it,” she continued. “Our commander in chief shouldn’t deride or insult our generals, retired or otherwise.”

Clinton had apparently planned to address the back and forth between Trump and the Khans during her first public remarks Saturday in Johnstown. CNN reported that a producer near the stage saw that portion of the script on Clinton’s teleprompter.

In the MSNBC interview Friday, Khizr Khan called on McConnell (R-Ky.) and Ryan (R-Wis.) — both of whom he called patriots and decent — to repudiate Trump’s comments about Muslims and other immigrants. “This is a moral imperative for both leaders, to say to him, ‘Enough.’ 

“The only reason they’re not repudiating this, his behavior, his threat to our democracy, our decency, our foundation is just because of political consequences,” he said in the interview.

Aides to Ryan and McConnell would not respond directly to the Khans, nor would they address what Trump had to say about the couple. Pence directed media inquiries to the Trump campaign.

Don Stewart, a spokesman for McConnell, pointed to a December statement in which McConnell said Trump’s suggestion of a Muslim travel ban was “completely and totally inconsistent with American values.”

AshLee Strong, a spokeswoman for Ryan, also noted the speaker’s past denunciation of the travel ban.

“The speaker has made clear many times that he rejects this idea and himself has talked about how Muslim Americans have made the ultimate sacrifice for this country,” she said.

Gearan reported from Johnstown, Pa., and Pittsburgh. Stephanie McCrummen and Mike DeBonis in Washington, John Wagner in Raleigh, N.C., and Philip Bump in New York contributed to this report.