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People are calling for T-Mobile to push out its adviser Corey Lewandowski after he mocked a 10-year-old girl with Down syndrome who was taken from her mother at the US-Mexico border.

Lewandowski, a former campaign manager for President Donald Trump, appeared on Fox News' The Story With Martha MacCallum on Tuesday night to talk about the administration's separating members of some families that cross the US-Mexico border.

Zak Petkanas, a Democratic strategist and fellow guest on the show, told the story of the 10-year-old girl being separated from her family.

.@Zac_Petkanas says on Fox News a 10-year-old girl with Down Syndrome was separated from her mother at the border.



Corey Lewandowski responds: "Womp womp." pic.twitter.com/cZMXWmwbjw — Jon Passantino (@passantino) June 19, 2018

Lewandowski responded with, "Womp, womp," a sound generally conveying a lack of empathy, or suggesting a person got what they deserved or failed.

"When parents commit crimes by coming into this country, regardless of who their children are, they are separated because we are a nation of laws," Lewandowski said on Fox on Wednesday, defending his earlier comment.

Lewandowski's comments prompted criticism on Twitter. Journalist and television host Megyn Kelly said in a tweet, "This man should not be afforded a national platform to spew his hate."

There is no low to which this coward Corey Lewandowski won’t sink. This man should not be afforded a national platform to spew his hate. https://t.co/M8adu7P2sf — Megyn Kelly (@megynkelly) June 20, 2018

Others urged T-Mobile to fire Lewandowski.

I understand @TMobile and @VP Mike Pence’s PAC are paying the depraved @CLewandowski_ as a consultant. In light of Corey Lewandowski’s recent chilling appearance on @FoxNews, it’s time for both to #FireCorey. Don’t hesitate to RT this far and wide.#BoycottTMobile — Steve Redmond (@sjredmond) June 20, 2018

"In light of Corey Lewandowski's recent chilling appearance on @FoxNews, it's time for both [T-Mobile and Vice President Mike Pence's PAC] to #FireCorey," said one tweet, utilizing a trending hashtag.

"Our hearts and prayers go out to this child and her family during this unprecedented and trying time," Sara Hart Weir, president of the National Down Syndrome Society, reportedly said in a statement.

Lewandowski responded to what he claimed was "fake news," saying he "mocked a liberal who attempted to politicize children as opposed to discussing the real issue, which is fixing a broken immigration system."

Lots of Fake News today. I mocked a liberal who attempted to politicize children as opposed to discussing the real issue which is fixing a broken immigration system. It’s offenseive that the MSM doesn’t want to talk about the fact these policies were started under Obama. — Corey R. Lewandowski (@CLewandowski_) June 20, 2018

T-Mobile didn't immediately respond to a request for comment.

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