There is the possibility of the assassins doing this as well. They are extremely careful not to leave traces, so if they did, they would be more likely to tailor them to a certain message. And as there seem to be assassins using similar techniques all across the peninsula, we cannot rule out that there is a large network of them - possibly enough to field a large enough group to pull off something like this.

[The monotone of his mental voice is a little shaky, like he might either be furious or being sick. ...Maybe both.]

Can you tell how many there were?