Donald Trump delivered a 90-minute speech in Alabama on Friday (September 22), which was reportedly in support of Senator Luther Strange who faces an upcoming primary election on Tuesday (September 26). Things took a left turn when Trump took aim at the National Football league and brought up NFL player/activist Colin Kaepernick.

At one point, he referred to Kaepernick as “son of a bitch.”

“Wouldn’t you love to see one of these NFL owners, when somebody disrespects our flag, to say, ‘get that son of a bitch off the field right now?,'” Trump said. “‘Out. He’s fired. He’s fired!'”

Twitter erupted with reactions to Trump’s remarks and many stood in solidarity with Kaepernick, who famously took a knee during the National Anthem during an August 2016 game against the Green Bay Packers.

Kaepernick’s mother, Teresa Kaepernick, also chimed in, writing, “Guess that makes me a proud bitch.”

Diddy, J-Live, El-P, Killer Mike, Ice-T, The Roots’ Black Thought and Questlove, Russell Simmons, Immortal Technique, and Talib Kweli, among others, took to social media to express their outrage on Trump’s comment.

Check out their reactions below.