Harvard has reportedly canceled acceptance offers to at least ten students after the university was alerted to offensive posts they made on social media. Admissions experts say such a move is unusual.

The Harvard Crimson reports the online chat took place in a private Facebook group, and included racial epithets and images mocking sexual assault and the Holocaust.  

One message joked that abusing children was sexually arousing, the Crimson reported. Another called the hypothetical hanging of a Mexican child “piñata time.”

The University, which does not address applicants’ statuses, has refused to comment, but it's believed the revocations are final.

"Colleges and universities don't make a habit to rescind admission offers," said Melanie Gottlieb, deputy director of the American Association of Collegiate Registrars and Admissions Officers, adding that Harvard’s decision surprised her.

"These kinds of things tend to occur when a student has had a significant change in their grade point average or if the institution has been notified of some sort of significant discipline issue," Gottlieb said.

Harvard, like most schools, reserves the right to cancel admission offers, and with the public nature of digital communication, admissions officers are counseling students to be careful about what they post online.