It's never been definitely known why five of the 19 al-Qaida terrorists met in Las Vegas over the summer of 2001 before four planes were hijacked.
The UK's Daily Mail newspaper published several photos taken in Paddock's room after the shooting. Hunting, recreational shooting and gun ownership is woven tightly into a lot of people's identities here. Authorities believe he killed himself.
Paddock was retired. He often visited Las Vegas to gamble and go to concerts, and he listened to country music, the Washington Post reported.
"(He was) very quiet, not sociable. His family said they don't know Stephen Paddock and had no knowledge of he and Marilou's relationship.
A hotel receipt has raised questions about whether the Las Vegas gunman was alone in his hotel room.
Jesus Campos noticed the door of Paddock's room was ajar and was shot in the leg when he opened it, prompting Paddock to stop firing at crowds below.
In Las Vegas, police responded quickly and effectively. He'll have to hug people, get their tears on his poorly fitted suits. It's also relatively easy to obtain a concealed-carry permit and there are no restrictions on semi-automatic weapons or large-capacity magazines.
Did killer have an accomplice?
Police say Paddock set up surveillance cameras in the hallway outside of his hotel room.
He only sought medical attention when ordered to leave by the police, Lombardo claimed.
Before targeting the Route 91 Harvest music festival, Paddock rented a room at a condominium complex overlooking the Life is Beautiful music festival, another downtown event held between September 22 to September 25.
The death toll now stands at 59, including the suspect, with 489 injured, confirmed Joseph Lombardo, sheriff of LVMPD.
"Our family, and all our extended family, the Danleys, have been getting death threats", his daughter said.
Barack Obama wept as he tried to soothe the nation after the 2012 Sandy Hook primary school shooting, George W. Bush told Americans that the "nation grieves" after a similar outrage at Virginia Tech university. "There were bloodstains everywhere".
Terrorists, as well as people deemed potential terrorists who are on the federal government's no-fly list, are prohibited from flying.
But the incident did spark a new debate about guns and gun control. Then he headed to the Las Vegas Metropolitan Police headquarters to visit with officers who had responded to the massacre. NPR's Kirk Siegler reports.
Danley lived with Paddock in Mesquite, Nevada, and was out of the country during the shooting.
SIEGLER: The early analysis is that Shepherd's hunch is probably right.
Investigators are trying to trace that money. The FBI is working with Philippine authorities to determine details.
The massacre has brought new attention to the world of high-limit video poker and casino comps where high-rollers are given all sorts of free items to keep them gambling. "So you didn't know if somebody was shot or if they were laying down".
Countless strangers have rallied to support victims, donating blood, money and supplies. Ian Bartrum is a constitutional law professor at UNLV.
The suspected gunman in the attack that killed 58 people and wounded hundreds more in Las Vegas Sunday night sent his girlfriend away to the Philippines in the days leading up to the attack.
Officials have reacted cautiously to an Islamic State group claim that Paddock was a "soldier of the caliphate" but while his motive remained unclear, the shooting instantly rekindled the divisive national debate on gun control.