The most common and most likely answer to this crossword clue is the 3 plus 3 letter word THE MOB
T
H
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M
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B
More clues leading to the result THE MOB
- Families departed — but not with us?
- Those people with nothing, British gangsters
- Border in future restricted for lot to which 20 in character belonged
- Criminalssteal without resistance
- Enemies of US love British gangsters
- Organised crime of those people undermined by old boy
- Objectively-speaking they died as gangsters
- Mobile home kept in large storage unit criminals organised
- A criminal organisation? Old boy’s supporting them
Buddy explains!

The straight part
We know that "A criminal organisation" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a criminal organisation = the mob.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.