Marshal's phone is confiscated (8)
I believe the answer is:
mobilise
'marshal's' is the definition.
('marshal'->'mobilize' is in my internal thesaurus and 'ize'->'ise')
'phone is confiscated' is the wordplay.
I cannot quite see how this works, but
'is' is within the answer.
'phone' could be 'mobile' (I've seen this before) and 'mobile' is located in the remaining letters.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for mobilise that I've seen before include "rally" , "18d [GET READY]" , "Prepare for war" , "Get ready for war" , "Make ready for action, troops for war perhaps" .)