(CNN) -- The Navy has replaced the top two leaders of the prestigious Naval Postgraduate School after a yearlong investigation into mismanagement and rule-breaking.
The school's president, Retired Navy Vice Adm. Dan Oliver, stepped down Tuesday, the Navy said. The military branch also replaced the school's provost, Dr. Leonard A. Ferrari.
An investigation initiated a year ago found that Oliver misused contracting procedures to sidestep federal salary limits and that both top leaders inappropriately accepted gifts from a private foundation that supports the school.
"Taken as a whole, we conclude President Oliver's conduct amounts to waste and gross mismanagement," the report states.
The investigation concluded that Oliver and Ferrari fostered an "atmosphere of defiance of statutory requirements and Department of the Navy rules and regulations."
Navy Secretary Ray Mabus appointed Rear Adm. Jan Tighe as interim president of the school, and the institution's vice provost will serve as acting provost, the Navy said.
Oliver had served as president since 2007, and Ferrari as provost since 2006.
The Naval Postgraduate School is in Monterey, California.