Grave letters from a rascal (3)

I believe the answer is:

rip

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

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for rip that I've seen before include "Shred" , "Tear roughly; turbulent water" , "Tear, rend" , "Tear; rough water" , "dissolute character" .)

I've seen this clue in the Evening Standard.

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