[Mule Skinner]

You could have civilians that would go into the prison to let the prisoners out as well. May be family, may be those that see any such institution as evil.

One I have often considered are zoos, since fam used to have exotic animal business. Folk would open the cages and let critters out. Not as many animal predators as there may be human predators, but these animals equate humans with food and would be fearless of us. With these animals being natural hunters, just about anything they come across most likely would be their next meal. Only takes one big cat you are unaware of to end your fight of survival.

I read a story some years ago that said
the lions got freed in Baghdad.

https://en.wikipedia.org/wiki/Pride_of_Baghdad#:~:text=Pride%20of%20Baghdad%20is%20a,an%20American%20bombing%20in%202003

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