On Oct. 1, 2017, a gunman perched on the 32nd floor of a Las Vegas hotel-casino unleashed a hail of bullets on an outdoor country music festival below, killing at least 58 people in the deadliest mass shooting in modern U.S. history. Almost 500 people were injured by bullets or in the ensuing chaos.Here's what we know about those who lost their lives.Hannah Ahlers was a mother of three from Murrieta, Calif.Heather Alvarado was a mother of three who lived in Utah.