Put together by director behind criminal activity in Belgium (9)

'put together' is the definition.
The answer and definition are not the same part of speech. However, adjectives and past participle verbs sometimes mean the same thing.

'director behind criminal activity in belgium' is the wordplay.
I cannot quite see how this works, but
'director' could be 'd' and 'd' is found in the answer.
'activity' could be 'racket' (racket is a kind of activity) and 'racket' is located in the answer.
'belgium' could be 'b' (international vehicle registration code) and 'b' is found in the answer.
A single letter 'e' remains which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).

'by' acts as a link.

Can you help me to learn more?