What the cur did when photographed (7)

I believe the answer is:

snapped

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'photographed' is the definition.
('snap' can be a synonym of 'photograph')

I can't explain the rest of the clue.

(Other definitions for snapped that I've seen before include "Spoke angrily" , "Broke; spoke irritably" , "Broke with a crack" , "What paparazzi did" , "Broke suddenly" .)

I've seen this clue in the Evening Standard.

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