Washington (CNN) Republican Rep. Adam Kinzinger of Illinois on Thursday morning called a chant that broke out at President Donald Trump's rally the previous night -- when the crowd yelled "send her back" as the President targeted Democratic Rep. Ilhan Omar of Minnesota -- "ugly" and "wrong" and said it "would send chills down the spines of our Founding Fathers."

"I deeply disagree with the extreme left & have been disgusted by their tone. I woke up today equally disgusted - chants like 'send her back' are ugly, wrong, & would send chills down the spines of our Founding Fathers. This ugliness must end, or we risk our great union," Kinzinger said in a tweet on Thursday morning.

Omar responded to the rally last night, saying on Twitter , "I am where I belong, at the people's house and you're just gonna have to deal!" Omar's message appeared next to a picture of her on the House floor with the American flag in the background.

The chant at Trump's rally comes as the President has repeatedly attacked Omar as well as the three other progressive Democratic congresswomen of color known as "The Squad" using racist language.

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