Aldean was in the middle of his performance when the bullets rained down on the crowd. Witness said tens of thousands of concertgoers screamed and ran for their lives, officials said Monday.
Authorities have identified the suspected gunman as Nevada resident Stephen Paddock.
U.S. records show Paddock lived in a three-year-old, 396,000 dollar (£297,554) two-bedroom home in the tiny desert community of Mesquite, 80 miles north east of Las Vegas near the Arizona state border.
Initial news reports, citing local hospitals, said there were at least 24 victims with gunshot wounds. Lombardo corroborated the cause-of-death at a press conference.
Lombardo said that he's confident that law enforcement has located a female person of interest, who was previously identified as Marilou Danley.
On her Facebook page, Danley described herself as a grandmother and mother, and her public profile showed pictures of her in various trips outside the United States, including the Philippines. His motives are unknown. Recordings and reports of the attack suggest the suspect was using an automatic weapon.More news: Mercedes unhappy despite extending lead in F1 title race
Eric Paddock says his brother Stephen, as far as he knew, had no religious or political affiliation.
"Honestly, at the start, we all thought it was probably an electronic thing, a malfunction, feedback or whatnot", he said. It was taken care of through the court system.
More than 10 rifles were found in the room, Lombardo said.
Police had located two cars that belonged to the suspect.
The shooter fired as many as 600 rounds in six or seven bursts with an automatic weapon for almost four-and-a-half minutes, media reports quoted police sources as saying.Video footage of the shooting showed thousands fleeing the venue in panic, causing stampedes, according to eyewitnesses.