Duke University is condemning the latest apparent act of racism on campus. Students protested throughout the day as authorities investigated who left a noose hung from a tree on campus.

Duke's president, provost and student leaders said the noose does not reflect the university's values, but some activists seized on the incident as a sign that the school was not a safe place for African-Americans, reports CBS News correspondent Jericka Duncan.

By the time many Duke University students woke up Wednesday morning, their social media feeds were buzzing with photos of the noose.

"The biggest thing was kind of just shock and a little bit of disgust," Duke student John Park said. "The idea that there are people on this campus that we go to school with, that we go to class with every day, that are capable of doing things like that."

Made of a slender yellow rope, it was found hanging near a building housing the center for multicultural affairs and other organizations.

"We are not afraid. We stand together," people said during a march.

About 300 students marched to condemn the violent symbol of racism. Many more joined Duke officials at an afternoon forum.

"Without dialogue and without having the knowledge, the ignorance that happens here on campus will prevail, National Pan-Hellenic Council president Jason Ross said.

The noose was discovered around 2 a.m. Wednesday and The Duke People of Color Caucus published the photos.

The group was formed in response to another incident two weeks ago when a black female student claimed she was taunted with the same racist chant made infamous by fraternity brothers at the University of Oklahoma.

On its blog, the anonymous Duke student group called their university "a hostile environment for any and all black people."

On Wednesday, students, faculty and staff denounced racism and tried to bring unity back to their fractured campus.

"Things like this can't happen, and we need to all be responsible for making this a space that's safe for all the members of the community," Duke adjunct professor Stefania Heim said.

There are about 6,500 full-time undergraduates enrolled at Duke, and about 10 percent of them are African-American. The noose incident comes as Duke's renowned basketball team is preparing for its NCAA final four game Saturday.