Senate Majority Leader John Thune (R-SD) received a barrage of critical comments Monday over a social media post honoring “Native Americans’ Day” in South Dakota, which became the first state in 1990 to replace Columbus Day with a holiday celebrating indigenous peoples.

“Today is Native Americans’ Day in South Dakota, an opportunity to celebrate the heritage and contributions of the Lakota, Dakota, and Nakota people,” Thune posted on X.