Paddock had positioned himself in a hotel room on the 32nd floor of the nearby Mandalay Bay hotel. He killed himself right before police entered the room.
Authorities found a cache of weapons inside his room, including 10 rifles.
It's the worst mass shooting in US history. At this point, nothing about Paddock's motives are known.
Here is some video of the carnage:
Prayers to all of the victims.