problem with the infected creatures

[nykysle]

I am a bit curious.

One can hide from the infected creatures for a long time and they never move on. One or two stood in front of the the armoury door arguing forever. And the one that showed up with the flashlight in Overture never moved away all the time I hid behind the desk.

Is this normal, do they have to be attacked or killed?
I currently don't have any weapons in Black Plague.