If violent crime increases generally, or if new types of violent crime emerge (e.g. the sexual violence labelled by child protection services as "local grooming"), or if rare types of violent crime become common (e.g. assaults using knives and acid) the public is rightly concerned and is curious about who's doing it and why.
This curiosity ought to the first duty of responsible law enforcement. And if they're not asking "who?", "why? and "where's the pattern?", they're not really up to their job, are they?
And if mainstream journalists are not pointing this clear dereliction of duty out, "holding their feet to the fire", "speaking truth to power" and all the other things these "courageous" champions of justice like to boast about, then they are not up to theirs, are they?