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The gunman responsible for the worst mass shooting in modern US history is believed to be a grandfather who lived in a remote desert home.
Stephen Paddock, 64, was named by police as the perpetrator who massacred more than 50 people from a 32nd-floor Las Vegas hotel room.
The Nevada native opened fire on the Route 91 Harvest Festival on the Las Vegas Strip late on Sunday.
His brother Eric Paddock told Mail Online from his Orlando, Florida, home that the family was "dumbfounded" by what happened.
He told the website: "He was just a guy. Something happened, he snapped or something."
US records show Paddock lived in a three-year-old, $US396,000 two-bedroom home in the tiny desert community of Mesquite, 128km north east of Las Vegas, near the Arizona state border.
The house is currently being searched by detectives, Clark County sheriff Joseph Lombardo told reporters.
Paddock is believed to have killed himself before a police SWAT team burst into his room at the Mandalay Bay Hotel and Casino, where at least 10 "rifles" were found, he added.
He said: "We have no investigative information or background associated with this individual that is derogatory.
"The only thing we can tell is he received a citation several years ago, and that citation was handled as a matter of normal practice in the court system."
Local media said Paddock had also previously lived in Reno, Nevada, California and Florida.
He lived in the property in Babbling Brook Court with Marilou Danley, 62, records show.
Described as 4ft 11ins and of Asian ethnicity, she was named as his "companion" and initially as a person of interest by police.
But Sheriff Lombardo later said she was out of the country at the time and they did not believe she was involved, although Paddock used some of her ID to get into the hotel, where he had been staying since September 28.