Authorities have identified Stephen Craig Paddock as the man who opened fire on a country music concert in Las Vegas late Sunday, killing at least 59 people and injuring more than 527 people. It’s the worst mass shootings in modern U.S. history.
Paddock, 64, of Mesquite, Nev., was found dead in his Mandalay Bay hotel room after the shooting. Police believe Paddock committed suicide as officers closed in.
Police have yet to determine a motive.
“I can’t get into the mind of a psychopath at this point,” Sheriff Joseph Lombardo said.
WATCH: At least 59 dead and 500 injured in mass shooting at Las Vegas music festival
The carnage started around 10 p.m. local time (1 a.m. ET) after the gunman smashed out the windows of his room and opened fire on a crowd of more than 22,000 people at the Route 91 Harvest country music festival, which was taking place across the road from the Mandalay Bay hotel on the famous Las Vegas strip.
Paddock checked into the hotel on Sept. 28, three days before the attack. Authorities said the Nevada resident was found with 23 firearms in his room.
It’s believed he acted alone.
“We believe there was only one shooter and that was Stephen Paddock,” Assistant Sherriff Todd Fasulo said Monday evening.
Earlier police said there were at least 10 found in his home in Mesquite, along with plenty of ammunition. Police also found ammonium nitrate, a common fertilizer that can be used to make explosives, in Paddock’s car.
The retiree had no criminal history in the Nevada county where he lived, police said Monday. A check of federal and state databases showed Paddock was not on law enforcement authorities’ radar, said Las Vegas Metropolitan Police Department (LVMPD) Sheriff Joseph Lombardo.
The so-called Islamic State group issued a statement on Monday saying Paddock was “a soldier” who had converted to Islam months ago, however, there is no evidence to support that claim. Authorities say they have found no indication Paddock was associated with any international terror groups.
The Department of Homeland Security said in a tweet that there is no “specific credible threat” indicating there will be similar attacks on other public venues in the U.S.
WATCH: Cellphone videos captures panic as shots ring out at deadly Las Vegas music festival shooting
Country music star Jason Aldean was performing when Paddock fired down at the concertgoers from the 32nd floor at the hotel, police said. Aldean was in the middle of a song when the shots came rapidly.
Video of the shooting then showed Aldean stopping and the crowd getting quiet as if they were unsure of what had just happened. The gunman paused and then fired another volley from the gold glass hotel-casino as more victims fell to the ground while others fled in panic. Some said they hid behind concession stands and others crawled under parked cars.
WATCH: Law enforcement analyst says equipment allegedly used by Stephen Paddock show a large degree of pre-meditation
SWAT teams quickly descended on the concert and the casino, and officers used explosives to get into the hotel room where they found the gunman dead, authorities said.
Police had initially been searching for a woman associated with Paddock as a person of interest; she was later located outside of the country. Authorities said Paddock may have been using the woman’s ID in some way.
“She was not with him when he checked in, we have discovered he was utilizing some of her identification. We have had conversation with her and we believe her, at this time, not to be involved,” said Lombardo.
Authorities are still looking into Paddock’s background and history, according to Lombardo, and officers are carrying out a search of his Mesquite home.
He was not believed to be connected to any militant group, Lombardo said. Police have not called the shooting a terrorist attack.
“We have no idea what his belief system was,” Lombardo said. “Right now, we believe he was the sole aggressor and the scene is static.”
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Mesquite, where Paddock lived, is located 128 kilometres northeast from Las Vegas, along Nevada’s border with Arizona. The city in Clark County is home to about 17,400 people, including several retirement communities, along with casinos and golf courses.
Public records for Paddock’s home — located in an upscale retirement community — show it was bought in January 2015 for just over $369,000. Paddock also owned a number of rental properties.
He was described Monday as a multimillionaire real estate investor who enjoyed travelling to Las Vegas so he could play high-stakes video poker.
His brother Eric Paddock, who lives in Florida, said he recently received a text from Stephen showing that he had won $40,000 on a slot machine.
“He was a guy who had money,” Eric said. “He went on cruises and gambled.”
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Paddock also had his pilot license and had at least one single-engine aircraft registered in his name.
Access to the Mesquite home and surrounding area was being blocked off by police on Monday.
“We haven’t had any run-ins with him,” said Officer Quinn Averett with the Mesquite Police. “We haven’t had any contact in the past.”
Police evacuated residents from nearby homes before they searched the gunman’s house.
“We had to prepare for the worst — what might have been, who might have been in the home,” said Averett.
An initial search of the home turned up ammunition, said Averett. Police also said they had located two cars that belonged to the suspect.
Paddock lived in Dallas from 2004 to 2012, police said.
“We have no idea. We’re horrified. We’re bewildered and our condolences go out to the victims,” he said in a brief telephone interview. “We have no idea in the world.”
Eric said Monday he had already spoken with police. The brothers spoke occasionally, Paddock said, adding that one of the last texts he received from his brother was simply checking in to ask how their elderly mother was doing.
While Eric Paddock said his brother owned some handguns and perhaps a hunting rifle, he was shocked to hear his brother was in possession of automatic weapons.
“He was not an avid gun guy at all. The fact that he had those kinds of weapons it… just where the hell did he get automatic weapons? He has no military background or anything like that,” Eric said.
Nevada does not require firearm owners to obtain licenses or register their guns.
There was zero indication his brother was planning such a senseless act of violence, Eric said.
“If there was anything I could have done I would have done it.”
While Stephen Paddock was not known to police, his father was a career criminal who spent years in prison and tried to run down an FBI agent with his car in Las Vegas in 1960.
Patrick Benjamin Paddock was a violent bank robber who was added to the Federal Bureau of Investigation’s Most Wanted list after escaping from a federal prison in Texas in 1968. An FBI poster issued after the escape said his father had been “diagnosed as psychopathic,” and warned that he was considered “armed and very dangerous.”
FBI records show he was “removed from the list when it was felt he no longer fit the Top Ten criteria.”
Their father was largely absent from their lives, Eric said of their father, “We didn’t know him.” He died in 1998.
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Among the dead in the Las Vegas attack is an LVMPD officer who was off-duty at the time. His name is being withheld pending notification of next of kin. There were also two on-duty officers injured, one of whom was upgraded recently from critical to stable condition. The other sustained non-life threatening wounds.
“Obviously this is a tragic incident. And one that we have never experienced in this valley,” Lombardo said.
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— With files from Reuters and the Associated Press
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