Former FBI agent believes motive for Las Vegas shooting will surface

The lead FBI agent for the Oklahoma City bombing said the motive behind the deadliest mass shooting in U.S. history will become clear.

“You can’t tell me that with this type of planning that took place, someone didn’t know what was about to happen,” said Danny A. Defenbaugh, who served 33 years in the FBI until he retired in 2002.

Defenbaugh said "something must have triggered" Stephen Paddock, 64, to gun down concertgoers from a hotel room high above the Las Vegas Strip.

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“It’s got to be a thorough investigation as far as trying to find a motive so you can catch the next one before it happens again,” said Defenbaugh, now a Dallas-based security consultant.

Investigators are looking at  an array of possible clues to the shooting that killed at least 59 people and injured hundreds more.

Florida resident Eric Paddock said his brother was wealthy and had made money as an accountant and property investor. He also worked at aerospace manufacturer Lockheed as an internal auditor.

News reports said Paddock was a high-stakes gambler. His girlfriend, Marilou Danley, had worked as a hostess at a casino in Reno.

Defenbaugh said theories such as Paddock suffering a gambling loss do not make sense. 

“Would you take it out on innocent people or would you take it out on the casino itself?” he said.

Detectives began the first full day of investigation in Las Vegas on the 15th anniversary of the Washington, D.C., sniper attacks. John Allen Muhammad and Lee Boyd Malvo were arrested after a three-week manhunt for killing at least 10 people and injuring several others.

That case, like the Las Vegas mass shooting, was uncharted territory for investigators.

“You know, that just blew the lid off of people investigators were trying to profile because at the time, there were no blacks in those types of killings,” Defenbaugh said. “But just like that case, something triggered it.”

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Defenbaugh said he and fellow investigators initially were unclear why Timothy McVeigh bombed the Alfred P. Murrah building in Oklahoma City in April 1995, killing 168 people and injuring hundreds of others. Then a TV reporter approached him with a videotape of Timothy McVeigh discussing the 1993 FBI standoff outside the Branch Davidians' complex in Waco, Texas.

Similar revelations will help investigators in Las Vegas try to make sense of the senseless.

“This was a random killing; it was slaughter,” he said. “This guy was some sort of anomaly.”