Students at the University of Pennsylvania are shaken after “a number of black freshman students” were unknowingly added to a group text message thread with racist rhetoric and imagery.

According to a statement from the university, the “GroupMe” account -- apparently controlled by a user based in Oklahoma -- contained “violent, racist and thoroughly repugnant images and messages.”

In screenshots obtained by the Daily Pennsylvanian, the campus newspaper, the account appeared to include depictions of lynchings; members were also called racially explicit terms.

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University officials and IT staffers are attempting to locate the exact origin of the account.

“I feel sick to my stomach,” Cavalry Rogers, an African-American UPenn student, wrote in a widely-shared Facebook post. “I don’t feel safe.”

Another student told The Daily Pennsylvanian that the incident was a blatant “instance of anti-black racism.”

Black students throughout @Penn's campus, like myself, have been added to this hateful GroupMe. I am petrified and all I want to do is cry. pic.twitter.com/DrqLvpXAW5 — Chidera (@chiderasiegbu) November 11, 2016

The University of Pennsylvania is President-elect Donald Trump’s alma mater.