Kambiz Fattahi, a Georgetown University graduate student who works for the BBC’s Persian Service, writes in a first-person essay that two campus security guards pulled him aside for questioning at last weekend’s graduate commencement.

An American citizen of Iranian descent, Mr. Fattahi writes that he was listening to “the inspiring keynote speech about America’s tradition of freedom” by the Harvard historian Bernard Bailyn when the security guards interrupted.

“Please come with us,” Mr. Fattahi reports being told. “You’re making some people here nervous.”

After being questioned, he was allowed to return to his seat, but the classmate he had come to see had already received her diploma. Georgetown, which prohibits racial and ethnic profiling, is reportedly investigating the incident. —Don Troop