Railways suffering regular cuts unfortunately (4)

I believe the answer is:

alas

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'unfortunately' is the definition.
('alas' is used to express regret)

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for alas that I've seen before include "Sad expression" , "Regretfully!" , "Sadly, unfortunately" , "Expression of grief or misfortune" , "Woeful expression" .)

I've seen this clue in The Sun.

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