McDonald’s said its continuing investigation into former CEO Steve Easterbrook’s conduct is examining whether he covered up improprieties by other employees alongside allegations of potential misconduct within the human-resources department.

McDonald’s filed suit against the former CEO following a tip that board chairman Rick Hernandez received last month about an alleged sexual relationship between Easterbrook and an employee. That tip also raised concerns about the HR department and possible improprieties by other employees, McDonald’s executives said. The company declined to provide details on allegations that it said involved the HR department.