Initially, before running towards the entrance of the building, where I could estimate the cries were coming from, I was a bit unsure whether there really was someone crying in there or if it was some kind of illusion magic set up by someone to trick me.
After some quick thought I suspected that that couldn't be possible however, because while considering the thought that the voice sounded similar to that of Hazel, I knew that it would simply be stupid for someone to use the voice of a person that's a zombie. 'Who would possibly fall for such a trap?' I figured, further thinking that if someone actually did, he was either prepared for a worse case scenario or was someone with alzheimer.
Worse case scenario and a logical one, what I imagined that would be was that the zombie Hazel was probably trying to lure people in the building so she could jump on them and eat them.