The father of a fallen Muslim Army captain who slammed Donald Trump at the Democratic National Convention last week said the Republican presidential nominee’s response to his emotional speech was “typical of a person without a soul” as Trump continued to defend his words.

Khizr Khan—whose son, Captain Humayun S.M. Khan of Virginia, died in Iraq in 2004 — had criticized Trump’s call to ban Muslims from entering the U.S. last Thursday while delivering a powerful speech at the Democratic convention.

Trump responded to Khan’s speech Saturday by saying he has “made a lot of sacrifices” by creating “tens of thousands of jobs.” The real estate mogul also asked whether Khan’s words were written by Democratic rival Hillary Clinton’s “scriptwriters” and questioned whether Khan’s wife Ghazala Khan was allowed to speak on stage as a Muslim woman.

“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. You tell me,” Trump had said in an interview with ABC News. “She was extremely quiet, and it looked like she had nothing to say.”

Khizr Khan told the Washington Post late Saturday that Trump’s response was “typical of a person without a soul.” And on Sunday he told CNN that Trump has a “black soul” and lacks empathy.

His grieving wife said she didn’t want to share a few words on stage over fears she would break down sobbing. “[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 when I saw the picture on my back, I couldn’t take it,” she told MSNBC on Friday. “And I controlled myself at that time. It is very hard.”

Khizr Khan said his wife broke down as soon as they were off camera. “The people inside, the staff, were holding her, consoling her. She was just totally emotionally spent,” he told the Post. “Only those parents that have lost their son or daughter could imagine the pain that such a memory causes.”

Trump on Sunday defended his response, saying it was about fighting terrorism. “Captain Khan, killed 12 years ago, was a hero, but this is about RADICAL ISLAMIC TERROR and the weakness of our ‘leaders’ to eradicate it!” he wrote on Twitter.

“I was viciously attacked by Mr. Khan at the Democratic Convention. Am I not allowed to respond? Hillary voted for the Iraq war, not me!” he said in another tweet.

Khizr Khan also told the Post that Trump’s words on Saturday “proves that this person is void of empathy.” “This is my country too,” Khizr Khan said. “He lacks awareness of these issues. He doesn’t realize there are patriotic Muslim Americans in this country willing to lay their lives for this country. We are a testament to that.”

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