The mass shooting in Las Vegas occurred at the Route 91 Harvest country music festival in an area with many famous establishments, near Mandalay Bay Casino, on the Las Vegas Strip.
Initial reports said two people had died and 24 were injured.
The incident occurred during a music festival when gunmen fired at a crowd with a rifle. Police chief Lombardo confirmed that a gunman was shot down.
Lombardo did not provide the identity of the deceased suspect, but confirmed that he fired from the 32nd floor of the Mandalay Bay hotel.
Police are hunting for the remaining shooter - identified as Marylou Danley - who is still in hiding.
Las Vegas police have asked people to avoid the area around the Mandalay Bay hotel, which has been partially blocked.
Authorities set up a center and checkpoint, closing part of the Strip.
Dozens of audiences fell down, screaming, while others ran away.
The shots went off for more than 30 seconds before the music stopped, then another round.
