A white tennis player at Appalachian State University in North Carolina has been suspended after recently exhibiting “derogatory and offensive” behavior towards a black opponent.

According to a statement released by the university, Spencer Brown, a freshman, was suspended indefinitely from the men’s tennis team after John Wilson, a black student athlete and senior class president from North Carolina’s A&T State University, tweeted that Brown said to him “at least I know my dad” during a match on Sunday. Wilson says that Brown also made other offensive remarks to him during the match, The Associated Press reports.

“Their coach responded by saying, ‘..we have a black guy on our team,'” Wilson wrote on Twitter.

Hey #NCAT this is Spencer brown, a tennis player at Appalachian state. During our match today, along with other racist comments, Spencer told me, “At least I know my dad.” Their coach responded by saying, “..we have a black guy on our team.”

Black twitter, do ya thing. pic.twitter.com/ZRN61zCU2n

— John Wilson IV (@jpheze) January 29, 2018

Appalachian State University addressed the situation in a statement, denouncing Brown’s behavior and assuring the public that such behavior is not acceptable at their university.

“After yesterday’s men’s tennis match, an Appalachian State student-athlete engaged in behavior that was derogatory and offensive,” reads the statement in part. “This student-athlete has been suspended indefinitely from the team, effective immediately, for violating the student-athlete discipline policy.”

School officials are still investigating the incident, App State’s athletics director Doug Gillintold the Winston-Salem Journal, including the possible involvement of Brown’s coaches. In the meantime, Gillin says that he’s called N.C. A&T Director of Intercollegiate Athletics Earl Hinton III to apologize for Brown’s behavior.

“There was a lot of people there that we’re still trying to figure out who was there and who saw or heard what,” Gillin told the Winston-Salem Journal. “But it didn’t take us long to know that this student-athlete of ours made this statement and therefore, we acted immediately.”

Wilson thanked his supporters on social media on Monday, writing in a tweet, “Thank you all for the help, this is something I’ve always dealt with being a black tennis player.”

Statement regarding men's tennis. https://t.co/pT0hqWZehy pic.twitter.com/8cXKztXfbD

— App State Athletics (@appstatesports) January 30, 2018