More details revealed about Las Vegas shooter's weapons

The gunman who opened fire on a crowd in Las Vegas had an arsenal of weapons worth tens of thousands of dollars, with at least one made-to-order firearm built by a high-end manufacturer.

. He began purchasing firearms in 1982 and had purchased more than 50 legally, according to Jill Snyder, special agent in charge at the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF).

Snyder told "CBS This Morning" co-host Norah O'Donnell that Paddock's purchases didn't set off any alarms at the ATF.

"We wouldn't get notified of the purchases of the rifles," Snyder said. "We would only get notified if there was a multiple sale, which would be two or more handguns in an individual purchase."

Snyder said there is no federal law requiring notification of sales of multiple semi-automatic rifles.

Christopher Sullivan, the general manager of Guns & Guitars in Mesquite, told CBS News correspondent DeMarco Morgan that he sold Paddock a rifle on Sept. 28, the same day he checked into the Mandalay Bay hotel in Las Vegas. Sullivan said Paddock had been a customer for about a year, and in that time the shop sold him five firearms.

"This morning over coffee I was having a moment in myself thinking that I may have very well been the last person to shake hands with that man,'" Sullivan said. 

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