GroupMe, the Microsoft-owned messaging app that was used for a racist cyberbullying attack last week at the University of Pennsylvania, said it removed the messages instantly and is investigating the case.

A number of black freshman students at Pennsylvania was targeted on Friday from a GroupMe account in Oklahoma. Multiple publications, including Philly.com, said the students were added to a list that referenced lynching in the subject and came from users with names like "Daddy Trump."

GroupMe, which is part of Microsoft's Skype unit, lets users send out group messages from their phones for free.

"As soon as we became aware of the chats taking place on GroupMe which violated our terms of service, we took action and removed the chats," a Microsoft representative said in an e-mailed statement Sunday night. "We're investigating to determine which user accounts will be suspended."

Since Republican Donald Trump, a graduate of Penn's Wharton School of Business, won the presidential election, there have been numerous protests across the country, opposing his expressed views on immigrants, minorities and women.