There are a few products I can recommend that work on odor, but ideally locationg and disposing of the dead animals will need to be done if possible.
The products that we use are Enzymatic Cleaners that break down odors:
Nature's Miracle: http://www.ilovenaturesmiracle.com/home/index.php
MisterMax Anti Icky Poo Starter Kit
You can also use powdered lime which can also help. This is some information on how to use Powdered Lime for odor control: http://www.ehow.com/how_5559407_use-lime-rid-odor.html
I hope this helps with the problem and gets the pace back in shape for your tenents.