Sen. John McCain, R-Arizona, sternly rebuked Donald Trump for his remarks about the family of a fallen U.S. Muslim soldier.
"In recent days, Donald Trump disparaged a fallen soldier's parents. He has suggested that the likes of their son should not be allowed in the United States -- to say nothing of entering its service," McCain wrote. "I cannot emphasize enough how deeply I disagree with Mr. Trump's statement."
He went on to say that he hoped Americans wouldn't think that the comments of the GOP nominee represent the sentiments of the Republican party and its candidates. And he suggested that he wouldn't be silent "simply because it may benefit others with whom I disagree."
McCain then retold the story of how in 2004 in Baqubah, Iraq, Army Capt. Humayun Khan sacrificed his own life to save the lives of his subordinates by ordering them away from a suspicious vehicle and running toward it himself, so that the car detonated before it reached the nearby mess hall where hundreds of soldiers were eating breakfast.
"I challenge the nominee to set the example for what our country can and should represent," the Arizona senator said of Trump.
"Arizona is watching. It is time for Donald Trump to set the example for our country and the future of the Republican Party," he continued. "While our Party has bestowed upon him the nomination, it is not accompanied by unfettered license to defame those who are the best among us."
While his was the strongest admonishment of his party's presidential nominee, more Republicans in the Senate have also criticized Trump for his remarks. Four more Republican senators--all of whom are facing tough re-election fights--are distancing themselves from Trump's criticism of Khan's family.
Sen. Ron Johnson of Wisconsin said that "Capt. Humayun Khan, and all the Americans who have made the ultimate sacrifice for our country, deserve our deepest respect and gratitude."
Sen. Rob Portman of Ohio said through a spokeswoman that he "does not agree with Donald Trump's remarks and believes that Captain Khan was an American hero who gave his life for his country."
Pennsylvania's Pat Toomey said, "The Khan family, like all Americans who lose loved ones in the defense of our country, deserve our gratitude and honor. Anything else is inappropriate." Toomey is the only one among the four who has not endorsed Trump.
Missouri Sen. Roy Blunt has given Trump a tepid endorsement, and he advised Trump to "focus on jobs and national security and stop responding to every criticism whether it's from a grieving family or Hillary Clinton." He went on to say that the Khans "deserve to be heard and respected."
Trump has repeatedly denounced the parents of Capt. Humayun Khan, after Khan's father, Khizr Khan, spoke at the Democratic convention last week. Khizr Khan said Trump's proposals would have barred his son from immigrating to the United States because they are Muslims.
Khan gave a blistering denunciation of Trump at last week's Democratic national convention, as his wife stood silently beside him last week on the Philadelphia stage. A photo of their slain son Humayun filled the screen behind them. Trump, last week questioned Ghazala Khan's silence at the convention and suggested that she was being silenced as a woman because of their Muslim faith.
It was none of that, Khan relayed to CNN. Instead, Khan said his wife told him: "You know my condition. When I see my son's picture, I cannot hold myself together."
"For this candidate for presidency to not be aware of the respect of a Gold Star Mother standing there, and he had to take that shot at her, this is height of ignorance," Khan said. "This is why I showed him that Constitution. Had he read that, he would know what status a Gold Star Mother holds in this nation. This country holds such a person in the highest regard. And he has no knowledge, no awareness."
Ghazala, for her part, has now publicly spoken out twice about her son since the convention, appearing on MSNBC Friday night and then publishing an editorial in the Washington Post Sunday.
Over the weekend, the Trump campaign blasted out press releases calling Captain Humayun Khan a "hero," while also warning against "radical Islamic terrorists" and responded to Khan's address by saying that "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."
Gov. John Kasich, Sen. Kelly Ayotte and GOP congressional leaders Mitch McConnell and Paul Ryan have also responded to Trump's remarks.
CBS News' Walt Cronkite contributed to this report.