The brother of the man identified as the gunman in what’s being called the deadliest mass shooting in recent USA history was at a complete loss early Monday to explain what might have precipitated the attack.

Police have named Stephen Paddock, a 64-year-old from Mesquite, Nevada, as the suspect who opened fire from a high-rise hotel on a country music concert in Las Vegas and killed more than 58 people in the worst mass shooting in recent U.S. history.

Mesquite, where Paddock lived, is located about 128 kilometres northeast from Las Vegas, along Nevada’s border with Arizona. The number of dead surpassed the death toll in the June 12, 2016, rampage at the Pulse gay nightclub in Orlando, Florida, where 49 people were slain.

Police are also searching for two vehicles registered to the suspect: a Hyundai Tuscon with Nevada plate 114B40 and a Chrysler Pacifica Touring with Nevada plate 19D40.

Country music star Jason Aldean was performing when Paddock fired down at the concertgoers from the 32nd floor at the hotel, police said.

JAMES ATOA/UPI/NewscomAt least 50 people have died and more than 400 were transported to hospitals in the wake of a mass shooting at an outdoor concert in Las Vegas. “Texas mourns and prays for the victims of this tragedy, and the entire Las Vegas Community, in this time of unimaginable pain”.

Police say Paddock acted alone, though a woman who lived at the same Mesquite, Nevada, address was sought by police earlier Monday, according to multiple media reports.

Watson says she’s never had a more crowded elevator ride in her life as guests crammed in, trying to make it to the safety of their rooms. He also had a home in Reno, in the east of the state, according to reports.

“We believe the individual killed himself prior to our entry”, Lombardo said.

Authorities in Mesquite said he was a “mystery”, and they had very little information about him. Lombardo said the LVMPD is interested in talking to a companion by the name of Marilou Danley, who was traveling with the suspect.

Reports of the shooting came first on Sunday night, when the Las Vegas Metropolitan Police Department reported an active shooter in the vicinity of the Mandalay Bay Resort and Casino on the Las Vegas strip.

“People started running over to the Tropicana [hotel], so we made a decision to run over to the MGM [Grand hotel]”, he said, as that’s where his mother and brother were staying.

Paddock owned two aircraft and held a pilot’s license, according to the “Today” show. “The only thing I can tell you is that the documents were regularly late”.

Canadian Monique Dumas said she was standing six rows back from the main stage when she heard gunfire for “four or five minutes”.