Can't remember title of martial arts/gangster film

[Guest NukeMeSlowly]

I believe it is a later 1970s/early 1980s era film. I am fairly certain it was Japanese. I saw it dubbed on "Kung Fu Theater" on Channel 5 in Southern California 20 odd years ago. As I (hazily) recall, its starts out with the police investigating a number of gangland killings where the victims are stabbed one time in the throat. You see the lead actor of the film getting briefed with a slideshow of pictures of the dead at police headquarters. At some point they suspect it might be an undercover cop they had infiltrate the mob doing the killings; I think he carries a cane with a concealed sword. There is a fight between that undercover cop and the lead actor where the lead character produces a small switch blade knife which has a ballistic blade (i.e. the blade shoots out and nails the undercover dude in the hand/arm). I know this is not a lot to go on but any help would be appreciated.

[Guest WalkOn]

Golgo-13: The Kowloon Assignment, starring Sonny Chiba, maybe? I don't recall Kung Fu Theatre/Drive In Movie showing to many Japanese films besides this one and Bullet Train. I could be wrong.