LAS VEGAS (KTNV) - It was chaos and terror Sunday night. A swarm for survival, as a gunman fired at thousands of innocent people at the Route 91 Harvest Music Festival.
Now, law enforcement has launched what it calls a "swarm" investigation, consisting of as many people and resources as possible to investigate the shooting and gunman Stephen Paddock.
"In this case, you're going to go until you get it all done because you don't want evidence to disappear," Brig Barker, of Red Rock Global Security Group, told 13 Action News via Skype.
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Barker has supervised multi-agency law enforcement investigations in the past and conducted an analysis of Omar Mateen, the gunman who killed 49 people and wounded 58 others at the Pulse Nightclub in Orlando.
Like Orlando, Barker said agents and officers in the Las Vegas investigation will work around the clock filing applications for search warrants for Paddock's records, retrace his steps as far and wide as possible and conduct interviews that, in some cases, could last several days.
During a news conference that ended within the last hour, the FBI confirmed the swarming.
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The FBI has deployed more than 100 personnel from across the nation to assist the Las Vegas division in this investigation, including victim-witness assistance, EAP counselors, evidence techs and technical assets.
"We don't want the whole family there. We don't want friends and spouses there. We want to have an individual by themselves," Barker said.
Perhaps the most critical interviews will be with Marilou Danley, Paddock's former girlfriend, who left the country.
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The investigation will focus not only on why the gunman wanted to kill so many innocent people, but how he did it, and if anyone is responsible for helping him.