I walked to the 2nd floor of police station in Dolina.Went in to a room with a narrow passage between two desks and tried to loot off one of the desk, not sure if it happened with the inventory screen open or right after I looted.
Heard a broken leg sound and character laid down on the floor. Can crouch but not stand up. Bottom left corner reports "legPainAche", however inventory screen does not report a fracture message (see attachment). Later I heard a zombie aggro'ing but not visible yet remained aggro'ed.
In conclusion, I suspect the structure though the zombie could potentially have been the culprit.