Las Vegas high-rise shooting scenario a security nightmare

A Las Vegas shooter's perch in a 32nd-floor hotel room overlooking 22,000 people jammed into a country music festival below is just the kind of nightmare scenario police dread in places where big crowds and high- rises mix.

From two broken-out windows of the Mandalay Bay Resort, Stephen Craig Paddock had an unobstructed view to rain rapid- fire bullets on the crowd, with few places for them to hide.

Survivors of Sunday night's bloodbath that left 59 people dead and more than 500 wounded repeatedly compared it to shooting fish in a barrel.

In places like New York, Chicago and Austin, Texas, where big events are planned in city streets in the coming days, police sought to reassure jittery residents Tuesday of some of the precautions they are taking to prevent just such a scenario.

New York City's police boss says that regularly includes sharpshooters with binoculars on rooftops scanning nearby building windows for potential threats, helicopters circling above with snipers of their own, and detectives making security sweeps of nearby hotels.

But he acknowledged there is only so much that can be done.

"We do understand," said NYPD Commissioner James O'Neill, "that no city or town in this country is completely immune to such unbridled hatred."

Added David Katz, CEO of Global Security Group, which conducts active-shooter training around the world: "The answer only really is, if there's a sniper, there's a counter- sniper."

But "you're not going to be able to deploy police units with sniper capabilities everywhere," Katz said. "There are, at some point, too many things going on, too many opportunities to stop them all. Unfortunately, if someone is intent on doing harm they will find a way to do it."

Chicago Mayor Rahm Emanuel, whose son will be among the 45,000 runners in the city's annual marathon Sunday, said emergency officials, including federal authorities, have conducted roughly a dozen workshops to talk through various scenarios and Chicago is prepared for "any eventuality."

"People don't just show up on marathon day and decide to run 26 miles. They train all year," Emanuel said. "That's also true of the Chicago police."

Despite assurances of a heavy police presence at this weekend's Austin City Limits music festival, expected to draw 75,000 people a day to the city's downtown, organizers were offering refunds to anyone uncomfortable with attending following the Las Vegas shooting.