Captive turns over red containers holding explosives (6,4)

I believe the answer is:

powder kegs

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'explosives' is the definition.
The definition and answer can be both man-made objects as well as being plural nouns.
Maybe there's an association between them I don't understand?

'captive turns over red containers' is the wordplay.
'captive' becomes 'POW' (prisoner of war).
'turns over' says the letters should be written in reverse.
'containers' becomes 'kegs' (keg is a kind of container).
'red' written backwards gives 'der'.
'pow'+'der'+'kegs'='POWDER KEGS'

'holding' is the link.

Can you help me to learn more?

I've seen this clue in The Irish Times.

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