On Friday, Republican Sen. Mark Kirk (IL) issued an apology for his remarks regarding his opponent Rep. Tammy Duckworth’s ethnic heritage.

“Sincere apologies to an American hero, Tammy Duckworth, and gratitude for her family’s service,” Kirk said on Twitter.

Twitter users did not accept his apology.

@MarkKirk How's that nasty, racist thing working out 4 you? 'Cause soon you'll be out of work & looking for a new job. It's called KARMA. pic.twitter.com/v0uOKzWioe

— J. Taylor (@PartyPrincessa) October 28, 2016

@MarkKirk you are a disgrace Who has no business in any government position. So glad you let your true feelings come out

— deb (@antiquer48) October 28, 2016

Let's face it @MarkKirk political expediency – you still hold the same #racist views against people like @TammyforIL @juliemason #ilsen https://t.co/OePCCUgByU

— Stephen Streiker (@84Suburban) October 28, 2016

@MarkKirk @JohnJHarwood Aoologizing for your words doesn't change what you've shown if your heart. You should be sorry for that.

— norm de plume (@CindyNormancin) October 28, 2016

An unbelievable, despicable racist comment hurled at a true American hero – wounded in combat. #MarkKirk – you disgust me. https://t.co/qh6RBvkXdG

— Udey Johnson (@UdeyJohnson) October 28, 2016

@MarkKirk let's see your wounds asshole. https://t.co/6GT3PVBO6S

— Lou Fortin (@louthelip) October 28, 2016

FUCK YOU, BIGOT https://t.co/OoC3aaP509

— SheriffFruitfly (@sherifffruitfly) October 28, 2016

One of the more moronic moments in this utterly moronic election #Election2016 #MarkKirk https://t.co/f0pHLcskHz

— Andy Stravers (@ajstravs) October 28, 2016

@MarkKirk @elisefoley you don't get to apologize. We heard you loud and clear.

— notrump (@33tuna) October 28, 2016

@MarkKirk Thanks for giving us something we can all agree on, even Trump…you, sir, are a loser.

— Kristina Witzling (@kwitzling) October 28, 2016

Are we surprised @MarkKirk is a piece of shit? https://t.co/1yPxalv8mY

— La Chingona (@SATANPLSS) October 28, 2016

@MarkKirk You can't take back a racist remark by thanking someone for their service. Shame on you. Tammy Duckworth deserves better.

— Scary Seahawk Lady👻 (@Hawknana_) October 28, 2016

@MarkKirk "When somebody shows you who they are, believe them". You're crystal clear who you are and we're voting you OUT!

— time4sanity (@time4sanity) October 28, 2016