Panic that wakes you up (5)

I believe the answer is:

alarm

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'panic' is the definition.
(alarm can mean panic or fear)

I can't explain the rest of the clue.

(Other definitions for alarm that I've seen before include "Anxious awareness of danger" , "Frighten or startle" , "A rousing sound in the morning" , "Wake-up call?" , "Safety bell or alert signal" .)

I've seen this clue in The Daily Express and The Mirror.

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