Note found amongst burnt remains of US sect (5)
I believe the answer is:
amish
'us sect' is the definition.
(the Amish are a religious community of the US)
'note found amongst burnt remains' is the wordplay.
'note' becomes 'mi' (as in 'do re mi').
'found amongst' means one lot of letters goes inside another (inserted letters are placed amongst others).
'burnt remains' becomes 'ash' (remains of a fire).
'mi' put inside 'ash' is 'AMISH'.
'of' is the link.
(Other definitions for amish that I've seen before include "Religious group" , "US religious community" , "those eshewing modern technology" , "Relating to a strict American sect" , "US sectarians" .)