PITTSBURGH — Carnegie Mellon University has suspended the operations and activities of a fraternity while allegations involving images “of a sexual nature” are investigated.

The university said in a statement Friday that the national fraternity organization also had suspended the Beta Theta Pi chapter.

Officials said a student notified them about alleged videos and pictures “of a sexual nature” taken in the fraternity house on the Pittsburgh campus and e-mailed to others.

A Pittsburgh newspaper says Dean Gina Casalegno told students in an e-mail that officials believe “a relatively small number of individuals are depicted.”

President Jared Cohon said in a statement that he’s not presuming guilt but is “shocked and deeply disappointed” by the allegations.

University police are investigating and have sought help from outside law enforcement.