Stephen Paddock: What we know about Las Vegas shooting suspect The suspected gunman behind the deadliest mass shooting in modern U.S. history was a 64-year-old Nevada resident who fired out of his room at the Mandalay Bay Resort and Casino before turning his gun on himself, police said. Las Vegas Police said Stephen Paddock was found dead when a SWAT team breached his room on the 32nd floor of the resort and casino, located across the street from the Route 91 Harvest Festival concert. He died of a self-inflicted gunshot wound just as police burst their way into the room, Las Vegas Metropolitan Police Department Undersheriff Kevin McMahill told the Las Vegas Review-Journal. Police found that Paddock was in possession of more than 10 rifles. Suspected Las Vegas shooter Stephen Paddock. (Eric Paddock/WOFL) Paddock checked in as a hotel guest on Thursday, Sept. 28 before the attack, which left at least 50 people dead and more than 400 injured, Clark County Sheriff Joseph Lombardo said. LAS VEGAS SHOOTING: DOZENS DEAD, HUNDREDS SENT TO HOSPITALS IN MASSACRE Lombardo added that police are investigating how Paddock got the weapons into the hotel and if he had been hiding them. "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." Responding officers used an explosive device to force the door open into Paddock's room, law enforcement officials told Fox News. Eric Paddock, his brother, told Fox 35 that his family was caught off guard by the attack. "An asteroid just fell on us," he said. Stephen went to college and started a business before retiring to the Las Vegas area because he liked gambling, Eric Paddock said. "He has no political affiliation, no religious affiliation, as far as we know," Eric Paddock also said to The Daily Mail. "Our condolences go to the victims and all their families." Federal law enforcement sources told Fox News that Paddock "was known to local authorities," in Las Vegas. But police in Mesquite, where Paddock lived, said he never had any run-ins with officers, the Desert Valley Times reported. Police initially sought a woman believed to be Paddock's roommate, Marilou Danley, as "person of interest." Detectives later made contact with her, and "do not believe she is involved with the shooting on the strip." TRUMP OFFERS 'CONDOLENCES' TO VICTIMS OF 'TERRIBLE' ATTACK Paddock was carrying some of Danley's identification when he was found dead in the hotel room, Lombard said. The pair lived in a retirement community in Mesquite, about an hour northeast of Las Vegas, and Danley was Paddock's girlfriend, Eric told The Daily Mail. Paddock apparently was the manager of the apartment complex -- which was being searched by police early Monday morning -- FOX 5 News reported. "He was just a guy," Eric Paddock told The Daily Mail. "Something happened, he snapped or something, he was just a guy." Property records show Stephen once owned a home in Viera, Fla., from 2013-2015, the Orlando Sentinel reported. Fox News' Jake Gibson contributed to this report.