2020 presidential candidate Sen. Kamala Harris has apologized for a video showing her laughing at a supporter describing President Donald Trump as “mentally retarded.”

The California senator apologized during an interview with CBS News and in a follow-up tweet, saying she didn’t hear what the man said in the moment.

When my staff played the video from my town hall yesterday, it was upsetting. 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. https://t.co/mNmo1hyNpW — Kamala Harris (@KamalaHarris) September 7, 2019

“I’m sorry. That word and others like it aren’t acceptable. Ever,” Harris said in a tweet.

Speaking with CBS, Harris said the term is “incredibly offensive and in 2019 you would think people would have a much better understanding of how hurtful a term like that can be.”

CBS’ Caitlin Huey-Burns also asked Harris if she heard what the man said, noting she didn’t correct him in the moment.

“I heard him talk about the other stuff and that came later … it wasn’t something that I heard or processed or in any way condone,” Harris said.

Watch above, via CBS News.

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