Story: CAPTAIN AMERICA#318 by Mark Gruenwald (writer) and Paul Neary (artist)
Synopsis: Death Adder, on the run, gets into a taxi. The driver is something of a yakker. In mid conversawtion, the driver pulls out a sawed of shotgun and fires and explosive bullet which passes through a front seat and into Death Adder. The driver removes a face mask and declares, "Justice is Served, Death Adder."
Does this tie into the Scourge storyline? More or less. This story begins the hunt for Scourge story, but this hit occurs before we see any of the organized attempts to stop Scourge in action.
Is this part of the main story? Pretty much since it's the opening scene of a storyline about Scourge
Comments: Oddly, Scourge says, "Justice is Served, Death Adder" instead of just 'Justice is Served." This is symptomic of some hits but not the majority of them, suggesting possible mannerisms of a particular Scourge
Another hit occurs in the same issue. See the post immediately following this one.