Crime Security Official Describes Challenge of Guarding Against Another 'Nightmare Scenario' Shooting Like Las Vegas "The guy had the perfect sniper's nest," a security official tells PEOPLE By Chris Harris Chris Harris Twitter Chris Harris has been a senior true crime reporter for PEOPLE since late 2015. An award-winning journalist who has worked for Rolling Stone and MTV News, Chris enjoys prog rock, cycling, Marvel movies, IPAs, and roller coasters. People Editorial Guidelines and Susan Keating Published on October 3, 2017 01:56PM EDT Share Tweet Pin Email Protecting the innocent in “soft target” environments like public concerts is the sort of thing homeland security planners lose sleep over because “there’s almost nothing you can do,” a security official tells PEOPLE. “This is the nightmare scenario,” the official says about the carnage at Sunday evening’s Route 91 Harvest country music festival in Las Vegas, which left at least 58 people dead and wounded hundreds of others in the deadliest mass shooting in modern American history. “The guy had the perfect sniper’s nest,” says the official, who is not authorized to speak to the press and spoke on the condition of anonymity. “He picked his target, and he picked his spot.” So-called “soft targets” are vulnerable public areas with high occupancy and limited protection. The security official tells PEOPLE the shooter, 64-year-old real estate investor and high-stakes gambler Stephen Paddock, likely spent weeks if not months planning Sunday’s deadly attack. According to authorities, Paddock opened fire from his 32nd-floor hotel room at the Mandalay Bay casino on the 22,000 concertgoers below. He was later found dead of an apparent suicide. Twenty-three guns were reportedly found with him. • Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter. Describing the shootings as reminiscent of the 1963 attack on President John Kennedy, the official likens the Las Vegas assault to an assassination. “Someone takes the high ground and picks off targets who don’t see it coming,” the official says. “A lot of care and planning went into both incidents. We studied this scenario and tried to learn from it.” This type of attack — from high ground — remains a vulnerability that needs to be addressed in some way, according to the official, though options are limited. “What are you going to do: put a bulletproof barrier around every building?” the official says. Ethan Miller/Getty Images What the Government Recommends Homeland security methods for large crowds typically include measures such as metal detectors, bag searches and bomb-sniffing dogs, the official says. Now, measures sometimes also include concrete barriers and sand-filled garbage trucks to block vehicle-ramming against pedestrians. The unexpected, though, is just that: “Some things you can’t reasonably plan for,” the official says. Scott McConnell, a Department of Homeland Security spokesman, tells PEOPLE the agency works with local government officials and private business “to provide expert counsel and recommendations about protective measures” that can be implemented at public venues. McConnell says those recommendations include maintaining closer relationships with local law enforcement. Businesses are further encouraged to “plan for how you would respond” to a deadly shooting spree. In addition, the DHS recommends employee training for potentially lethal situations, McConnell says. Any suspicious activity should also be reported to law enforcement. • PEOPLE’s special edition True Crime Stories: 35 Real Cases That Inspired the Show Law & Order is on sale now. Describing the department’s recent efforts in Nevada, McConnell says: “Over the last year, DHS has conducted 17 critical infrastructure assessments with partners in the Las Vegas area. During that same time period, DHS has conducted eight counter-improvised explosive device and risk mitigation training courses for 161 public and private sector security partners. “Since 2011, DHS has held seven active shooter workshops in Nevada, including five workshops in Las Vegas and two in Reno. The workshops drew close to 750 participants from federal and local government as well as nonprofit and private organizations.” The DHS also maintains “a central web page dedicated to active shooter preparedness for citizens, human resources and security professionals and law enforcement,” with “links to in-depth resources, ranging from online training to awareness materials to planning guidance and classroom training information.” A fact sheet with a number of resources for communities and businesses is available here. David Becker/Getty Images In a statement following the shooting, the chairman of MGM Resorts International, which owns the Mandalay Bay, said, “Our primary focus and concern in the hours since the shooting has been cooperating with law enforcement and taking actions to support the victims and their families, our guests and employees.” “We’re grateful for all who have helped — first responders, the police and citizens who have acted in countless ways to assist. While information is still being gathered we are beginning to hear stories of great courage and humanity,” the chairman’s statement continued, deferring further questions about the investigation to law enforcement. “We’re working with law enforcement in every way possible,” the chairman said, adding, “Please pray for all the victims of this horrific event, our Las Vegas community and all our employees who are working tirelessly to provide support at a very difficult time.” The FBI has said that, so far, there is no connection between Paddock and international terrorism, while a federal counter-terrorism source told PEOPLE, “Something triggered this guy. He seemed to act out of nowhere. What happened: Was it domestic problems? Mental illness? Revenge? Or did he join ISIS? We have to consider everything.” As investigators continue to probe a possible motive for the attack, it also remains unclear how, exactly, Paddock was able to bring so many weapons apparently undetected into the hotel. “He likely didn’t just walk into the lobby with the weapons on a cart,” the security official says. “Probably he broke them down and carried them up in pieces and assembled them inside his room.” A hotel most likely would not want to do bag-checks on guests or install security guards to swab peoples’ hands, as is sometimes done at airports, the official says. “They’re not going to wand everyone who shows up at the hotel.” Even a metal-detector might have been useless in this case, according to the official: “In some places, people carry weapons. It’s not against the law.” How to Help and Learn About Loved Ones Friends and family are asked to report missing people believed to be connected to the shooting using the hotline 1-800-536-9488. Anyone with photo or video evidence of the shooting is asked to call 1-800-CALL-FBI. The city of Las Vegas has established a Family Reunification Center to help connect relatives with the more than 500 people who were injured. In addition, city officials urged those locally who wish to donate blood to visit one of two donation centers operated by United Blood Services, either at 6930 W. Charleston in Las Vegas or at 601 Whitney Ranch Drive in Henderson, Nevada.A victims’ fund has been started on GoFundMe by Steve Sisolak, the Clark County, Nevada, commission chair. Other groups providing relief include the local chapter of the American Red Cross and the National Compassion Fund.