59 people are dead and more than 527 are injured after a mass shooting in Las Vegas

A gunman killed at least 59 people and injured 527 others on the Las Vegas Strip late Sunday night.
The gunman opened fire on concertgoers at the Route 91 Harvest country music festival.
A SWAT team stormed his room, but found Paddock already dead.
Police recovered 16 rifles from Paddock's hotel room. The Clark County Sheriff said more than 18 additional firearms were found at Paddock's home in Mesquite, Nevada, including some explosives and "several thousand rounds" of ammunition.

At least 59 people were killed and more than 527 were injured Sunday night in Las Vegas in the deadliest shooting in modern US history.

A gunman opened fire from the 32nd floor of the Mandalay Bay Resort and Casino, aiming into a tightly packed crowd of thousands below who were attending a country music festival.

The shooter, armed with what appeared to be at least one automatic weapon, used the elevated vantage point to fire into the crowds across the Las Vegas Strip at the Route 91 Harvest festival, where Jason Aldean was onstage.

Officers identified the shooter as Stephen Paddock, a 64-year-old man from Nevada. They believe he was the only attacker, and that he killed himself before they arrived.

Police completed a search of Paddock's hotel room and his home in Mesquite, Nevada, which is around 80 miles from Las Vegas. At least 16 rifles were found in the hotel room, law-enforcement officials said during an afternoon press conference. Clark County Sheriff Joseph Lombardo said investigators recovered an additional 18 firearms at Paddock's home in Mesquite, Nevada as well as some explosives and "several thousand rounds" of ammunition.

Investigators also found ammonium nitrate in Paddock's car at the Mandalay Bay, and possibly tannerite, Sheriff Lombardo said.

A;SWAT team was preparing to search another home in northern Nevada.

Soon after the shooting, which began at 10:08 p.m. PDT, a SWAT team stormed the building, forced their way into his hotel room, and found the gunman already dead.

A statement from ISIS claimed that the attack was their doing, and that Paddock converted to Islam "a few months ago." The FBI contradicted this claim, saying that Paddock had "no connection with an international terrorist group."

In a press conference Monday morning, Lombardo said the figures for the numbers dead and injured following the shooter may still increase.

Who was Stephen Paddock?

Stephen Paddock was retired and had no criminal record before the attack, Reuters reported. He used to work as an accountant, and his brother described him to CNNas "a wealthy guy playing video poker ... on cruises."

A Washington Post report characterized Paddock as a quiet man who occasionally came to Las Vegas to gamble or catch concerts, was a former resident of Texas, and held a hunting license in Alaska.

Eric Paddock, the shooter's brother, told CBS News that Stephen was "not an avid gun guy at all."

"The fact that he had those kind of weapons is ... just ... where the hell did he get automatic weapons? He has no military background or anything like that," Eric Paddock said. "He's a guy who lived in a house in Mesquite and drove down and gambled in Las Vegas."

Paddock was divorced, according to CNN, and his ex-wife resides in Los Angeles. The two divorced 27 years ago after a six-year marriage and have not been in contact in years, the report said.

Benjamin Hoskins Paddock, the shooter's father, was a well-known bank robber and on the FBI's Ten Most Wanted list from 1969 to 1977, CNN reported.

Benjamin Hoskins Paddock was a diagnosed psychopath, according to the FBI, and he was convicted of "bank robbery, automobile larceny, and confidence game."

Eric Paddock said he died several years ago.

The bureau's poster on the elder Paddock cautioned that he had committed armed robberies before, had "suicidal tendencies," and "should be considered armed and very dangerous."

Stephen Paddock owned two aircraft and held a pilot's license, according to the "Today" show. Paddock had worked for a predecessor company of Lockheed Martin, the giant defense contractor that builds planes.

Lombardo said officers had spoken to a woman, Marilou Danley, described as Paddock's roommate. She was outside the United States, he said, and officers believe she was not involved in the attack.

"We have no idea what his belief system was," Lombardo told reporters. In a subsequent press conference, Lombardo said "I can't get into the mind of a psychopath at this point."

The Daily Mail quoted Paddock's brother Eric as saying he and his mother were "in shock" and "dumbfounded" after finding out about the shooting. According to the Daily Mail, Eric Paddock described his brother as a normal guy who must have "snapped."

How it unfolded

Paddock had been staying at Mandalay Bay since September 28, four days before the shooting, Lombardo said. Police believe he booked the room Danley's ID.

Footage posted on social media showed the moment shots started to hit the crowd, which police estimated was around 22,000 people.

The singer Jason Aldean, who was onstage with his band at the time of the attack, later said in an Instagram post that the shooting was "beyond horrific" but that he and his crew were safe.

Here is one video uploaded by a journalist named Josh Caplan that shows screaming concertgoers trying to get away. Viewers may find parts distressing:

Photographs showing the concert area after most people had fled showed a victim covered in blood on the ground.

Another video shows the shooting from a different vantage:

Lombardo said it was too early to comment on the potential motivations of the attacker, aside from ruling out terrorism.

He added that two off-duty police officers were killed in the violence, while another two were injured.

Our thoughts & prayers ... @ Mandalay Bay Resort

Part of the I-15 freeway, which runs parallel to Las Vegas Boulevard, also known as the Las Vegas Strip, was closed but has since been partially reopened.

The manager of "Guns and Guitars, Inc.," the Mesquite gun store that sold firearms to Paddock, released a statement on Monday expressing condolences for the families of those who were injured and killed.

"Mr. Paddock was a customer and purchased firearms from our store; however, all necessary background checks and procedures were followed, as required by local, state, and federal law," the statement said. "He never gave any indication or reason to believe he was unstable or unfit at any time."

The manager concluded the statement by saying that they are cooperating with local and federal law enforcement "in any way we can."

The death toll makes the massacre the deadliest shooting in modern US history, surpassing the attack on the Pulse nightclub in Orlando, Florida, last year that claimed 49 lives.

This story is developing.