Arizona city’s overlooked by spies from Mediterranean region (9)
I believe the answer is:
phoenicia
'mediterranean region' is the definition.
(ancient Mediterranean region)
'arizona city's overlooked by spies from' is the wordplay.
'arizona city' becomes 'phoenix' (capital of Arizona).
'overlooked' suggests deleting specific letters.
'by' becomes 'x' (multiplication sign).
'spies from' becomes 'cia' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'phoenix' with 'x' removed is 'phoeni'.
'phoeni'+'cia'='PHOENICIA'
(Other definitions for phoenicia that I've seen before include "Middle Eastern region historically" , "Historic Middle East state" , "Ancient land in Lebanon and 5 dn" .)