Old Russian putting out island fire (4)

I believe the answer is:

sack

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'fire' is the definition.
(dismiss someone from their job)

I don't understand the rest of the clue.

(Other definitions for sack that I've seen before include "Container for coal etc" , "Plunder; wine; bag" , "Large bag; dismiss" , "Dismiss; an old wine" , "Fire the large bag?" .)

I've seen this clue in The Independent.

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