They also didn't mention finding clothing, or humans, or or cigarette butts in the alley, or anything else. Clearly it was of note that no weapon was found, otherwise they probably wouldn't have mentioned it. Of course, this is the press we're talking about, so it's possible that this incident didn't even happen and they're making the whole thing up to rally hate against the cops. It's entirely possible that this woman was part of a drug trafficking ring and the reporter didn't feel compelled to disclose that part.
So you're right, it really could be anything and here I go, getting sucked into what the press reports when I know damn good and well that they lie to further an agenda and create social strife.