Hell Is a City & Carry On Cabby
Carry On Cabby (1963) was perhaps my earliest 'favourite film' and I've enjoyed it ever since I was about age 6. What I only noticed this year is that the final sequence is a homage to a similiar sequence in Hell Is a City (1960). It wasn't the visuals which tipped me off, although they certainly felt familiar. It was the music which was of a similar jauntier style to that used in the more serious crime thriller. In Hell Is a City, the police make a cordon around where the criminals are holding an illegal gambling game. In Carry On Cabby, Sid instructs his fellow cabbies to "Fan out across the heath and move in. Fan out and move in!" by which manoeuvre they surround and capture the crooks.
Scenes from Hell Is a City (1960)

The gamblers begin to make a run for it.

The police cordon moves in.
Scenes from Carry On Cabby (1963)

The taxi cordon moves in.

The crooks are caught.
Hell Is a City quickly fell into obscurity so it's no wonder this reference was lost on later audiences. A shame, since it's a great movie, featuring the sights and sounds of 1959 Manchester (when it was filmed).