Manchester, New Hampshire (CNN) Sen. Kamala Harris apologized Saturday following criticism that the California Democrat and presidential candidate laughed and responded, "Well said," to a lengthy question from a voter who had called President Donald Trump's actions "mentally retarded."

Harris' presidential campaign account tweeted an apology, calling a video of the incident that was circulated on social media "upsetting," and denied she had heard the offensive term.

"I didn't hear the words the man used in that moment, but if I had I would've stopped and corrected him. I'm sorry. That word and others like it aren't acceptable. Ever," she wrote on Twitter.

The questioner at the candidate's Londonderry, New Hampshire, town hall on Friday identified himself as being from Chennai, India, the same hometown as Harris' mother, and said he had spent "all this effort" to live the American dream and then Trump was elected.

"Somehow a racist bigot gets into the White House and then he says if you're not my color you need to go back to your own country," said the man, who spoke with a thick accent. "So I am scared for this country. I am scared for the people of color in this country."

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