The motive of the gunman responsible for the deadly mass shooting in Las Vegas remains a mystery, as authorities raised the death toll to 59 people and said they had discovered explosives and ammunition at the man’s house and in his car.
Officials on October 2 said at least 527 people had been injured in the attack, which police say started late on October 1 when Stephen Paddock opened fire with an automatic rifle from the 32nd floor of the Mandalay Bay hotel toward an outdoor country music festival.
Authorities said the 64-year-old man fired for several minutes before he killed himself as officers stormed his room, where 17 guns were found.
Clark County Sheriff Joseph Lombardo said officers searching his house in the Nevada resort town of Mesquite had discovered more than “18 additional firearms, some explosives, and several thousand rounds of ammo, along with some electronic devices we're evaluating at this point."
Lombardo also said several pounds of ammonium nitrate -- which can be used to make explosives -- were found in Paddock's car.
Mesquite is about 130 kilometers from the gambling, entertainment, and tourist city of Las Vegas.
Police called the attack the largest mass shooting in modern U.S. history and possibly ever in the country.
President Donald Trump called the shooting "an act of pure evil" that has brought the country together in "sadness, shock, and grief." He said he would travel to the city on October 4.
The extremist group Islamic State (IS) later claimed responsibility for the attack through its Amaq news agency and said the shooter had converted to Islam “a few months ago.” It provided no evidence.
However, the FBI said the shooter had no connection to an international terrorist group.
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Lombardo, when asked about a potential motive for the shooting, said he could not "get into the mind of a psychopath at this point."
Paddock's brother, Eric Paddock, said Stephen Paddock was a multimillionaire and a big spender at casinos, where he often received free rooms and meals.
Asked by reporters at his Florida home why his brother would have gone on the shooting rampage, Eric Paddock said, "I can't even make something up. There's just nothing."
Authorities said they have located 62-year-old Marilou Danley, who apparently was Paddock's roommate. Lombardo said the woman was traveling in Tokyo at the time of the shooting and that she will be interviewed when she returns to the United States.
The death toll surpasses the record number of 49 people killed by a gunman at a nightclub in Orlando, Florida, in June 2016. The perpetrator of that attack, who was killed in a shoot-out with the police, had pledged allegiance to IS, which later claimed responsibility.