University of Oklahoma (OU) President David Boren seems to be making good on his promise of swift justice in the school's racist fraternity chant investigation.

In a statement Tuesday afternoon on his official Twitter account, Boren said he expelled two students for "playing a leadership role in the singing of a racist chant in connection with an SAE fraternity event."

A student group known as OU Unheard first posted a video to Twitter Sunday night showing students on a bus shouting a chant that suggested black students would never join the Sigma Alpha Epsilon (SAE) fraternity. In the video, it appears that a few students are standing in the aisle leading the chant, but their identities have not been publicly disclosed.

Video contains offensive language.

Boren responded to the video within hours and the next day held a press conference in which he kicked the OU Kappa chapter of the SAE fraternity off campus. He also promised the school's investigation would seek possible punishments for any students identified to have participated.

"I have emphasized that there is zero tolerance for this kind of threatening racist behavior at the University of Oklahoma," Boren said in his statement, per ABC News. "I hope that the entire nation will join us in having zero tolerance of such racism when it raises its ugly head in other situations across our country. I am extremely proud of the reaction and response expressed by our entire university family - students, faculty, staff, and alumni about this incident. They are 'Real Sooners' who believe in mutual respect for all. I hope that students involved in this incident will learn from this experience and realize that it is wrong to use words to hurt, threaten, and exclude other people. We will continue our investigation of all the students engaged in the singing of this chant. Once their identities have been confirmed, they will be subject to appropriate disciplinary action."

In addition to addressing students at a demonstration on the Norman, Okla. campus, Boren also addressed the issue on CNN.

"Sooners are not racists. They're not bigots," he said. "They are people who respect each other and care about each other."