Officials warned students to secure in place after a man alleged to be armed was seen near the campus' main flag pole, headed toward a student housing area known as Mesa Court.
Campus officials said they found the man and that normal activities on campus resumed about 3:15 p.m.
"He had a gun, I don't know what kind," campus spokeswoman Cathy Lawhon said.
Earlier this month, a "viable threat of violence" prompted the university to cancel a student government meeting where student legislators planned to discuss whether to override the veto of a controversial measure that would have banned the American flag — and all other flags — from a small area of the campus.
Tuesday's alert from police arrived as an induction ceremony for the campus' new chancellor, Howard Gillman, was scheduled to begin.
The program continued at the Barclay Theatre with the doors locked and nobody allowed in or out.