Where did you see that? Are you sure?
The Krinkov AK-74 (the weapon Osama Bin Laden played with during his interview) is illegal to import into the US (except, inevitably, for USG examples) and isn't chambered for .223, but for an even smaller Russian subcaliber. It's a full-auto, short-barreled assault rifle/entry gun about the size of an MP-5. It wouldn't be a sniper's second or third choice, except "maybe" as a backup weapon.
Cops are also hot on the theory that multiple teams are doing the killing