US city manhunt disturbed hard-to-find element (9)

I believe the answer is:

lanthanum

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'element' is the definition.
(lanthanum is a kind of element)

'us city manhunt disturbed' is the wordplay.
'us city' becomes 'LA' (Los Angeles).
'disturbed' indicates an anagram (the order of letters is disturbed).
'manhunt' with letters rearranged gives 'nthanum'.
'la'+'nthanum'='LANTHANUM'

'hard-to-find' acts as a link.
I am not very happy about this link. It may belong to another bit of the clue.

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