Mirrors Edge Easter Egg - Strange Drawing

In the level New Eden mall, to get into the mall itself you will have to crawl through a vent and will find yourself in a room with a truck in the centre and boxes stacked against the wall in big yellow racks. Climb on top of the truck and you should find a rather crude and odd drawing of what appears to be a mouse in a cage surrounded by tiny armed police with a pair of eyes overlooking it all. I believe this ties in to the other egg about the the janitor and his mouse.