Bomb threats forced tens of thousands of people to flee college campuses in Texas and North Dakota on Friday, and campus safety experts were continuing to investigate the threats -- both of which proved false -- throughout the day.

The Federal Bureau of Investigation saw the threats as “largely local matters,” special agent Jason Pack said in a telephone interview from Washington. “There’s nothing we know that links the threats to something else.”

The Austin campus of the University of Texas was shut for hours, as was the campus of North Dakota State University in Fargo. Officials ordered the evacuations as precautionary measures, and the schools resumed operations later in the day.