Stephen Paddock, the man whose Las Vegas shooting rampage killed 58 people and left more than 500 injured, bought 33 guns in the past year, a law enforcement official said Wednesday.

Some of Paddock’s gun purchases date back more than 20 years, but authorities have determined that more than 30 of the firearms were acquired in the past 12 months, the official said.

The official who is not authorized to comment publicly said that most of the recent purchases were rifles. Authorities have been closely examining the buying spree in an effort to determine what drove the 64-year-old man to launch the deadliest shooting in modern American history.

Under federal law, gun stores are required to report multiple handgun purchases to the Bureau of Alcohol, Tobacco, Firearms and Explosives but not multiple rifle purchases.

The lack of notification for multiple rifle purchases creates a loophole where people can stockpile assault weapons, similar in design to those used by the military and police SWAT teams, with little federal detection, said David Chipman, a former ATF special agent and senior policy adviser at Americans for Responsible Solutions, which advocates for stricter gun rules.

Over the years, ATF agents have tried to get the rule expanded to long rifles, as a way to crack down on gun trafficking, he said. In 2011, the agency was authorized to mandate notification of multiple rifle purchases in four border states — Arizona, California, New Mexico and Texas — for six years. But overall the rule still only applies to handguns.

"This is a question of national security," Chipman said. "It doesn't make sense. This policy hurts law enforcement."

He added: "The weapons we are selling in America now are weapons used by tactical law enforcement and the military."

A key difference between weapons available to the public and those used by the military is that the military can obtain fully-automatic weapons, or those which fire continuously on a single trigger pull. Fully-automatic weapons, which includes machine guns, are tightly regulated by the federal government and illegal to purchase in certain states, unless the weapon was made before 1986 and meets other federal guidelines.

But devices known as "bump stocks" can be purchased by the public and allow gun owners to fire semi-automatic weapons nearly as fast as fully-automatic ones, without government oversight, Chipman said.

Paddock had similar devices attached to 12 semi-automatic rifles that allowed them to mimic fully-automatic gunfire, said Jill Snyder, ATF special agent in charge. ATF reviewed the technology, which has been around for less than a decade, and determined they were legal.

Don Turner, president of the Nevada Firearms Coalition, the state’s NRA association, said pro-gun-law groups are always quick to propose stricter gun rules after mass shootings, even before all the information has been gathered on the incident.

Stricter gun laws would probably not have stopped someone like Paddock from committing mass murder, he said.

"You can think emotionally or you can think logically," Turner said. "We need to really logically look at what happened to see if there are any solutions."

Records of Paddock's weapons purchases have been drawn from Nevada, Utah, California and Texas, where investigators are engaged in a far-flung effort to gather purchase records and in-store surveillance video to determine if others may have accompanied him. Authorities, however, believe Paddock acted alone when he fired on a concert crowd from a corner suite on the 32nd floor of the Mandalay Bay Hotel.

Investigators also have tracked a bulk ammunition purchase to Arizona.



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Paddock, who killed himself after the massacre, also used surveillance cameras to monitor police approaches to his room at the Mandalay Bay high-rise — including a camera he positioned in the peephole of the door.

“I anticipate he was looking for anybody coming to take him into custody,” Sheriff Joseph Lombardo said.

During the Sunday night rampage, a hotel security guard who approached the room was shot through the door and wounded in the leg.

“The fact that he had the type of weaponry and amount of weaponry in that room, it was pre-planned extensively,” Lombardo said, “and I’m pretty sure he evaluated everything that he did and his actions, which is troublesome.”

While Paddock's motive remains unclear, authorities were putting together a more complete picture of his work history and past. Paddock worked as a letter carrier for the U.S. Postal Service, an IRS agent and in an auditing department over a 10-year period.

A spokeswoman for the Office of Personnel Management told The Associated Press on Tuesday that Paddock’s employment included about two years as a mail carrier from 1976 to 1978.

After that, he worked as an agent for the Internal Revenue Service for six years until 1984. And then he worked a defense auditing job for about 18 months.

He graduated from college in 1977 from Cal State Northridge and also worked for a defense contractor in the late 1980s.

Contributing: John Bacon, USA TODAY

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