Word of warning about crime, initially, from the police (5)
I believe the answer is:
force
'police' is the definition.
(the force can refer to the police force)
'word of warning about crime initially' is the wordplay.
'word of warning' becomes 'fore' (I am not sure about this - if you are sure you should believe this answer much more).
'about' indicates putting letters inside.
'initially' says to take the initial letters.
The first letter of 'crime' is 'c'.
'fore' enclosing 'c' is 'FORCE'.
'from the' is the link.
Can you help me to learn more?
(Other definitions for force that I've seen before include "Lean on" , "cascade of water" , "Royal Air - -" , "Powerful effect or influence" , "Dynamism" .)