Fellow capturing hearts in Belgian city (5)
I believe the answer is:
ghent
'belgian city' is the definition.
(I've seen this before)
'fellow capturing hearts' is the wordplay.
'fellow' becomes 'gent' (I've seen this before**).
'capturing' indicates putting letters inside.
'hearts' becomes 'h' (abbreviation used in card games e.g. bridge).
'gent' enclosing 'h' is 'GHENT'.
'in' is the link.
(Other definitions for ghent that I've seen before include "City of northwest Belgium, known for its cloth industry" , "source of good news" , "Belgian city (from which the "good news" was brought to Aix)" , "Flanders city/port" , "European city" .)