one in Las Vegas, 2 shooters with one dead apparently - no idea how many they've managed to kill.
There was a saying I saw once that "it's never two shooters" as it's quite common for multiple shooters to be reported at the start of incidents like this but mostly it turns out to be just the one.
It was speculated that because of gunfire echo in built up areas it can sound like shots from multiple directions which is what causes the confusion.