In early August, Paddock booked a room at Chicago's 21-story Blackstone Hotel that overlooked the park where the Lollapalooza alternative music festival was being held, though there's no evidence he actually stayed there, a law enforcement official said Thursday.
Stephen Paddock called a Chicago hotel he had booked for Lollapalooza back in August to tell them that he wanted someone to call if, before check-in, he couldn't get a view room - a room that overlooked the venue.
"We are aware of the media reports and have been in communication with our federal partners".
Officials have struggled to find a motive for why Paddock, a retired real estate investor who liked to gamble, took at least 10 suitcases' worth of firearms and ammunition to the 32nd floor of the Mandalay Bay Resort and Casino and opened fire on a crowd of concertgoers gathered below. A few hours later, when 64-year-old Stephen Paddock opened fire on the crowd from the nearby Mandalay Bay hotel, killing 58 people, those thousands were left fleeing for their lives, with no care for the possessions they are now recollecting.
In addition to Chicago and Boston, Paddock may have considered another location in Las Vegas for his massacre.
Gov. Charlie Baker also says he's aware of the reports but couldn't discuss further because of the ongoing investigation into the mass shooting.
Ms Danley was out of the country at the time of the attack and said Paddock sent her to see her family in her native Philippines.More news: Game 6: Michigan State at Minnesota
Sheriff Lombardo said Paddock had been "living a secret life, much of which would never be fully understood".
Officials are also investigating the gunman's finances.
Wynn said a scenario like Paddock's "would have triggered a whole bunch of alarms here".
ABC News and NBC News also report Paddock may have scouted sites in Boston.
Police were reviewing video shot at the high-rise to check Paddock's movements.
The weekend before the deadliest mass shooting in modern US history, Paddock rented a high-rise condo in a building that overlooked the Life is handsome alternative music festival, said Clark County Sheriff Joseph Lombardo, who offered no other details about what led Paddock there.
FBI Deputy Director Andrew McCabe said he was surprised Paddock had provided so few clues, and that has proved challenging.