The most common and most likely answer to this crossword clue is the 4 letter word NABS
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More clues leading to the result NABS
Buddy explains!

The straight part
We know that "Arrests/more than one lock-keeper in person" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case arrests/more than one lock-keeper in person = nabs.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.
What does NABS mean?
NABS verb- To seize, arrest or take into custody (a criminal or fugitive).
- To grab or snatch something.
- A single-serving package of crackers, usually filled with peanut butter. Snack crackers.