False witness in Somalia rearrested (4)
I believe the answer is:
liar
'false witness' is the definition.
(thesaurus)
'in somalia rearrested' is the wordplay.
'in' indicates a hidden word.
'LIAR' can be found hidden inside 'somalia rearrested'.
(Other definitions for liar that I've seen before include "One telling untruths" , "Worse than a thief" , "Teller of untruths" , "Tale-teller" , "Dissembler" .)