Keen reporter's start to the day (5)

I believe the answer is:

mourn

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'keen' is the definition.
(I've seen this in another clue)

I can't explain the remainder of the clue.

(Other definitions for mourn that I've seen before include "Feel sorrow for death or loss" , "Grieve for a death" , "Show sorrow at death" , "Express sadness" , "Keen" .)

I've seen this clue in The Times.

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