Detectives carrying around a bug (6)
I believe the answer is:
cicada
'bug' is the definition.
(cicada is a type of insect)
'detectives carrying around a' is the wordplay.
'detectives' becomes 'CID' (abbreviation for Criminal Investigation Department).
'carrying' is an insertion indicator.
'around' becomes 'ca' (circa).
'cid' placed around 'ca' is 'cicad'.
'cicad'+'a'='CICADA'
(Other definitions for cicada that I've seen before include "Insect with a high- pitched drone" , "Noisy bug" , "Chirpy type" , "The insect produces a high-pitched sound" , "Chirpy insect" .)