Became an issue (5)
I believe the answer is:
arose
'became an issue' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for arose that I've seen before include "Came about" , "appeared" , "Followed" , "''. ... by any other name would smell as sweet'' (Romeo and Juliet)" , "Sprang up" .)