Republican Rep. Liz Cheney laid into leaders in her own party on Monday.
"The House GOP leadership has enabled white nationalism, white supremacy, and antisemitism," Cheney said in a tweet. "History has taught us that what begins with words ends in far worse."
Cheney's tweet was posted less than 48 hours after a suspected white supremacist carried out a mass shooting at a Buffalo, New York grocery store.
Ten people died in the attack and three others were wounded. Authorities said all but two of the victims are Black.
The FBI is investigating the shooting as a racially-motivated attack and a hate crime.
Republican Rep. Adam Kinzinger also called out a member of Republican leadership.
He tweeted that Rep. Elise Stefanik "pushes white replacement theory," which the accused Buffalo shooter reportedly cited as a reason for carrying out the attack.
The theory essentially says that there is a plot to diminish the influence of White people by replacing them, possibly with non-white voters or immigrants who could reshape the political landscape.
Stefanik released a statement Monday that said she is "heartbroken" and "saddened" by the shooting in Buffalo.
One of Stefanik's advisers added that the congresswoman has "never advocated for any racist position or made a racist remark."