'I am appalled': 2 prominent Republicans delivered blistering rebukes of Trump's attacks on the Khan family

Republican Sens. Lindsey Graham of South Carolina and Kelly Ayotte of New Hampshire delivered blistering rebukes of Donald Trump on Sunday for his attacks against the family of slain Muslim American soldier Humayun Khan, who was killed serving the US during the Iraq War.

"This is going to a place where we've never gone before, to push back against the families of the fallen," Graham said in a statement to ABC. "There used to be some things that were sacred in American politics - that you don't do - like criticizing the parents of a fallen soldier even if they criticize you."

Graham, who was at one time a 2016 presidential hopeful, has not endorsed Trump.

"If you're going to be the leader of the free world, you have to be able to accept criticism," the South Carolina Republican said. "Mr. Trump can't. The problem is, 'unacceptable' doesn't even begin to describe it."

Ayotte, who's said she will vote for Trump, said she was "appalled" by the Republican nominee's attacks. The New Hampshire senator's husband is an Iraq War veteran.

"There is no greater sacrifice than to lay down one's life for their country, and that's the sacrifice that Captain Humayun Khan made fighting to defend our freedom and our constitutional rights," Ayotte said in a statement. "He was a true American hero. The Khan family deserves nothing less than our deepest support, respect, and gratitude, and they have every right to express themselves in any way they choose."

"I am appalled that Donald Trump would disparage them and that he had the gall to compare his own sacrifices to those of a Gold Star family," she continued.

Trump suggested Sunday morning that he could not understand why he was earning scorn for questioning the pair of Gold Star parents who slammed him during a speech before the Democratic National Convention in Philadelphia on Thursday.

"I was viciously attacked by Mr. Khan at the Democratic Convention," the Republican nominee for president asked in a tweet. "Am I not allowed to respond?"

Khizr and wife Ghazala Khan, the parents of Humayun, offered a powerful rebuke of Trump on the final night of the DNC.

In an eight-minute speech, delivered by Khizr, the family questioned whether the real estate magnate had ever read the US Constitution or sacrificed anything for his country.

Trump hit back on Saturday, suggesting Ghazala was not permitted to speak because of her Muslim religion. The billionaire further argued that he had indeed sacrificed for his country, saying he created jobs.

Trump's remarks were widely condemned and the billionaire eventually began walking them back. In a Saturday night statement, he called the Khan's son a "hero to our country" and tried to shift the issue to "the real problem" which he argued was "the radical Islamic terrorists who killed him."

Khizr Khan said Sunday that Trump's questions about his wife represent the "height of ignorance."

Ghazala Khan also wrote an op-ed in The Washington Post saying she didn't speak at the DNC because she finds it too painful to think about her son.

"Without saying a thing, all the world, all America, felt my pain," she wrote.

Indiana Gov. Mike Pence, Trump's running mate, pushed out a statement late Sunday in an attempt to clear up the attacks.

Pence said he and Trump believe Khan "is an American hero and his family, like all Gold Star families, should be cherished by every American."

"Captain Khan gave his life to defend our country in the global war on terror," the Indiana governor, who is Trump's running mate, wrote. "Due to the disastrous decisions of Barack Obama and Hillary Clinton, a once stable Middle East has now been overrun by ISIS. This must not stand."

"By suspending immigration from countries that have been compromised by terrorism, rebuilding our military, defeating ISIS at its source and projecting strength on the global stage, we will reduce the likelihood that other American families will face the enduring heartbreak of the Khan family," he said. "Donald Trump will support our military and their families and we will defeat the enemies of our freedom."

Oliver Darcy contributed to this report.