Detailed Instructions: Given a sentence and two mentions from the text (arguments), indicate a phrase (a verb or noun phrase) that describes the relationship between the provided arguments.
Problem:Sentence: 'Darfur Rebels Say Sudanese Army Attacked Their Bases VOA 06 Sep 2008 -- Rebels in Sudan 's Darfur region say they have come under heavy attack by government troops with many dead and injured .', Argument/Subject 1: 'darfur', Argument/Subject 2: 'sudan'
Solution:
be region of