Murderous Ghosts: what was your terrible human violence?

I've only run Murderous Ghosts once.  The reason I don't run it more often is that I have trouble imagining "terrible human violence" in the sub-basements of an old factory.  Can people chime in with theirs?

In the game I ran, a textile factory was being staffed by illegal immigrants.  When the factory owner found out he was under federal investigation, he locked the gates and set fire to the place, burning everyone alive in a misguided attempt to hide the evidence.

In the game I played in, the factory was already in ruins when a mother abandoned her 5-year-old twin children there, unwilling to care for them any longer.  When she returned months later with a change of heart to look for them, the feral children killed and ate her.

What else?  I'd like to run this game more often, but I have trouble thinking of stuff...

best,
James

My favorite so far that I've used is that some psychopath was torturing/killing animals in the factory. It let me introduce ghosts of all sorts of different animals as the player made their way through the factory, eventually encountering the ghost of the killer. Works especially well at wigging out the player if they're an animal lover.

I go with one of three basic concepts:
A. the factory's built on an old burial ground, possibly plague or native or slave or pauper
B. premeditated industrial "accident"
C. crime of passion

Then I look at the player's list:What's the worst thing this place reminds you of?
1 Betrayal
2 Sorrow
3 Cruelty
4 Madness
5 Revenge

Then I cross-reference following what the player chooses, for example:
A1 The ghosts are plague victims who followed a charlatan to the factory in hopes of being safe from the illness - no such luck, and now they want you dead too because you "carry the illness!!!"
A2 The factory was once pressed into service as a make-shift hospital. The ghosts are those victims who refused to leave their dying loved ones and now want you to stay there and take on the role of their beloved.
A3 Massacre by another tribe, followed by disturbed burial grounds when the building went up, leads to not a peaceful place at all.
A4 The poor mad mental patients were dumped here when they died. Some of them were not quite dead. All of them were quite mad. Now they are mad and undead.
A5 Here is where the master killed the slave, and here is where the slave's ghost killed the master. Both now continue to act out their violence.