I seen a raven flying over the highway with a live duck in its talons before, about two minutes later we seen the duck headed the other way with the raven in hot pursuit.
There's no doubt in my mind.
Also, Ive seen many magpie's on the edge of the paved roads across from farmers houses on the way to drumheller and back to calgary. They know that roadkill is food, and that animals get hit by cars to become roadkill. I believe they are smart enough that they are trying to lure the farm cats (which you can often see stalking them from across the road) to come out on the pavement. This might be speculaltion, but ive seen it a fair bit out that way.
And while im headed off topic,Ive heard of crows circling game during hunting season, they see hunters and game and soon after there is a gut pile enough times. Eventually they circle the moose or deer waiting for a meal to show up. Although you gotta be careful its something a bear killed and will aggresively defend.