"You're saying in both cases the victims knew the killer."
Your victim would certainly know something was wrong, whether or not he remembered what he'd done.
A13 The victims of poison gas did not know what hit them.
I think the victim knew he was about to be killed and meant the police to see it.
The police also said they did not know if the victims, none of whom were identified, knew one another.
The victim might not even know, were she alive to tell.
I would say that the victim never knew what struck him.
Nor was it apparent how the victims knew one another.
When it comes to conflicts, the victims know this better than anyone.
Only he and the victim knew that it had happened.