What does the cryptic crossword clue "Like some alloying — city police hypersensitive, we hear (11)" mean?

The wordplay uses a homophone (sounds like). MET (Metropolitan Police) sounds like ALLERGIC The answer is METALLURGIC.

Like some alloying — city police hypersensitive, we hear (11)

Times Cryptic #28633 | 1 Down | 2023-06-19 flower