Ghosts at the old edmonton sun building?

Have any of you worked at the old edmonton sun location and know of any ghosts that may have haunted that building? I'm working there this year as a scare actor for deadmonton and two of us scare actors (myself being one of them) believe we may have seen a ghost. It just looked like legs that ran past us, sounds goofy I know but I'm fairly certain I saw what I saw and so is my coworker. Then again my vision was slightly obscured so I'm not entirely certain of what I saw but it looked like it ran past me.