The videos were taken at around 4 a.m. Monday at the Washington, D.C., college, the police said, and show a figure moving through school property. The person's face is not clear in the footage.
The bananas were found on the same day that Taylor Dumpson, a black woman, started her tenure as the first black woman president of the American University Student Government.
It’s unclear how many bananas were found.
The acronym for Dumpson's Alpha Kappa Alpha sorority, "AKA," was written on some of the bananas, according to a report in The Eagle, a school newspaper.
Alpha Kappa Alpha is among the nine major, predominantly black Greek-lettered fraternities and sororities.
Dumpson addressed the incident in a memo that started with the phrase "Being first isn't easy."
"This is not what I imagined my first letter to you all would be, Dumpson wrote. "In my first message to the student body, I would have wanted to talk about accountability, transparency, accessibility, and inclusivity. Now more than ever, we need to make sure that members of our community feel welcomed and above all, safe on this campus."
American University is 55 percent white, according to College Factual, a company that keeps statistics about universities. The school is a little over 6 percent black.
Others at the school expressed outrage over the incident.
University President Neil Kerwin Tuesday night addressed students in an effort to calm concerns about the incident, with some students marching in protest afterwards, ABC Washington affiliate WJLA-TV reported.
Kerwin also said in a statement, "The crude and racially insensitive act of bigotry reported this morning is under investigation by AU Campus Police with assistance from the D.C. Metropolitan Police Department (MPD) and other AU offices and senior officials."
"We strongly condemn what happened; will do all that we can to find those responsible; and ask that anyone who may know of those involved to please step forward and contact Public Safety."
One student, Lale Herguner, told WJLA, "I really hope they find who did this because it’s terrible. A lot of people want answers and they deserve answers."
Campus police are offering a $1,000 reward for information leading to the suspect.