London borough in distress (6)
I believe the answer is:
harrow
I believe this clue is a double definition.
'london borough' is the first definition.
(I know that Harrow is London borough)
'distress' is the second definition.
(something harrowing is distressing)
'in' acts as a link.
(Other definitions for harrow that I've seen before include "Agricultural frame for breaking up soil" , "Equipment used in ground-breaking" , "Equipment provided for ground-breaking" , "Break up (ground) - distress (feelings)" , "Break new ground" .)