The Las Vegas shooting suspect managed to smuggle multiple weapons into his hotel room, turning it into a "fortress," former FBI Assistant Director Chris Swecker told CNBC on Monday.
At least 58 people were killed and 515 injured after a gunman opened fire from his Mandalay Bay room on more than 22,000 concertgoers in Las Vegas on Sunday. Police say the suspect, 64-year-old Stephen Paddock, then killed himself.
"He turned that place into a fortress, with multiple firing positions, lots of ammunition and at least 8 to 10 high-velocity shoulder-fired assault weapons," Swecker said in an interview with "Power Lunch."
He envisioned a setup that allowed the shooter not to have to reload but just move on to the next weapon.
And accuracy wasn't necessary, he said.
"Typically when you're on fully automatic you're not very accurate. But here they are all cued up in a mass, and they don't know where the shots are coming from. And all you have to do is just aim in a general direction."
Police told The Wall Street Journal that the shooter appears to have used a fully automatic rifle. Law enforcement authorities discovered a cache of at least 18 other firearms in the shooter's hotel room where he fired upon those below, the Journal reported.
Las Vegas Metropolitan Police Department Sheriff Joseph Lombardo said the suspect brought the weapons in on his own and that employees were in and out of the room and "nothing nefarious was noted."
— CNBC's Michael Sheetz contributed to this report.