Deleting Extra Files from Project Manager

Recently, I uploaded a new Word document into my RoboHelp project which contains a table. When I did this, I expected that it would show up as a new topic. But in addition to the new topic (Assessment Tool Icon Guide), a folder appeared with three gif files.

Why did this occur? Additionally, is there a way to delete these files? Is there a way to prevent this from happening to give the Project Manager a cleaner look, since we'll be importing it into our web application?