A University of Oklahoma fraternity will close and its members have been suspended after video purportedly showing some of its members taking part in a racist chant was posted online late Sunday.

The national organization of Sigma Alpha Epsilon said that an investigation had verified the contents of the 10-second video, which showed a group of men on a charter bus chanting the slogan "There'll never be a [n-word] in SAE." The chant also referenced lynching. 

"We apologize for the unacceptable and racist behavior of the individuals in the video, and we are disgusted that any member would act in such a way," the organization said in a statement. "This type of racist behavior will not be tolerated and is not consistent with the values and morals of our fraternity."

The Oklahoma Daily, the university's student newspaper, reported that it had received a tip about the video's existence in an e-mail Sunday evening. It was later posted on YouTube by Unheard, a black student group at the university. It wasn't immediately clear how the video was obtained, or where and when the incident took place.

University President David Boren said late Sunday that he had been informed of the video and that the university was conducting an investigation to determine if students were involved. 

"If OU students are involved, this behavior will not be tolerated and will be addressed very quickly," Boren said. "This behavior is reprehensible and contrary to all of our values."

Boren joined students at a rally Monday morning on the Norman campus, calling those who took part in the chant "disgraceful." 

"Real Sooners are not bigots, real Sooners are not racist," Boren said. 

The Daily reported that the on-campus fraternity house was vandalized with spray paint early Monday, moments after people carrying suitcases exited the building. Anonymous members told the Daily that they had received death threats by e-mail and through their Facebook accounts.

Some students and faculty at the university joined in a prayer circle on campus where they watched the video late Sunday. The Unheard group announced that it had planned an on-campus demonstration for 7:30 a.m. local time Monday. 

The Associated Press contributed to this report.