Circle of death (bug)

[SirensLure]

So not sure what happened to cause it but I am guessing people bumping into people maybe. I converted my dirt prison to a nice grass one and had over a 1000 workers on it (kinda wish I could of just paid a one time fee to a land scaping company). Once I completed the job I noticed a hallway that just had a bunch of guys running in circles come to find out it was workers, gardeners, and janitors bumping into one another the works trying to move wood, gardeners trying to plant trees, and janitors trying to clean the spot of death. It wasn't a small hallway (4-5 meters wide) but they kept in their infinite circling forcing me to fire them all and slowly add workers until I got one wiling to clear out offending items (which had fallen on one another which I believe help cause the circle of death).