Driver Noah Gragson has been suspended indefinitely and will not participate in NASCAR's Cup Series race on Sunday due to his "actions" on social media, according to NASCAR and his team, Legacy Motor Club.

A screenshot circulating on social media purports to show Gragson's Instagram account had liked a meme mocking George Floyd, a Black man who was killed by a White police officer in Minneapolis in 2020. Neither NASCAR nor Legacy Motor Club specified the reason for the suspension and CNN has not independently verified the post.

Gragson apologized in a post on Twitter on Saturday.

"I am disappointed in myself for my lack of attention and actions on social media," Gragson said. "I understand the severity of this situation. I love and appreciate everyone. I try to treat everyone equally no matter who they are. I messed up plain and simple."

Legacy Motor Club suspended Gragson indefinitely and said in a statement Saturday that his actions "do not represent the values of our team." Gragson will be replaced by driver Josh Berry for this weekend's Cup Series race at Michigan.

NASCAR "fully supports" the suspension of Gragson, it said in a statement, and added his actions on social media violated "the Member Conduct section of the 2023 NASCAR Rule Book" when issuing the suspension.

CNN has reached out to NASCAR for more information.

The 25-year-old Gragson, who is in his first year in the Cup Series, is ranked 33rd in points and has no top-10 finishes this season.