Donald Trump is receiving backlash for mocking a New York Times reporter who has a physical disability.

At a campaign rally in South Carolina this week, Trump was discussing his much-refuted claim that he had personally witnessed Muslims celebrating after the 9/11 terror attacks. Trump referenced an article that Serge Kovaleski had written in the Times that would appear to support his claim. Kovaleski, who has a congenital joint condition, says he has no recollection of anyone claiming that "hundreds of thousands" of people were seen celebrating.

According to the Washington Post, "Trump appeared to mock Kovaleski's physical condition; the reporter has arthrogryposis, which visibly limits flexibility in his arms. 'Now, the poor guy -- you've got to see this guy, 'Ah, I don't know what I said! I don't remember!' Trump said as he jerked his arms in front of his body."

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Kovaleski has covered Trump since the late 1980s. "The sad part about it is, it didn't in the slightest bit jar or surprise me that Donald Trump would do something this low-rent, given his track record," Kovaleski told the Post.

Trump issued his own statement to the Post, in which he denied knowing Kovaleski. "I have no idea who this reporter, Serge Kovalski [sic] is, what he looks like or his level of intelligence. I don't know if he is J.J. Watt or Muhammad Ali in his prime -- or somebody of less athletic or physical ability," Trump said, according to the Post. "Despite having one of the all-time great memories I certainly do not remember him."