Hotel pool parties that helped super-fuel the dance-music DJ craze in Las Vegas over the past several years could be vulnerable to the same type of attack that have left at least 59 people dead and more than 500 injured at a country music festival Sunday night (Oct. 1), artists and other industry officials tell Billboard.

In the wake of the attack, some DJs that spin at the popular pool parties called for hotels to increase security measures, including 9/11-style bag searches at check-in and metal detectors at the entrance doors at the MGM’s Wet Republic, the Wynn’s Encore Beach Club, the Cosmopolitan’s Marquee Dayclub and the Caesar’s Drai’s Beachclub, among other outdoor venues. The deadly shooting spree, in which the gunman fired upon the 22,000 festival attendees from a 32nd floor room at the Mandalay Bay Resort and Casino overlooking the festival grounds, exposed the vulnerabilities of Vegas' popular day parties, which often take place at communal swimming pools surrounded by looming hotels with hundreds of rooms.

“What makes me angry is the helplessness,” says Morgan Page, a DJ who drove past the country music festival on the way to the airport the day before the shooting after spinning at a pool party at the Mandalay Bay’s Daylight. “You can’t defend from an attack like this. I will still play shows, but may have to re-evaluate security options.”

Other DJs echoed his determination that the show must go on. But they also expressed concern about potential copycats.

“It's a sad day when we need metal detectors at hotels, but this is the state of our world at the moment, and if hotels feel they need to step up security at check in, I would fully support that,” says Eva Shaw, a DJ who regularly performs at pool parties at the MGM and the Cosmopolitan.

Until Sunday, attacks on pool parties seemed implausible; Las Vegas hotels are known for their world-class private security, and the pool clubs are generally built fairly far from hotel guest windows for noise-control reasons. And most Las Vegas hotel windows, especially at newer venues, are sealed shut. “You couldn’t even throw a hot dog out the window at somebody in the pool,” says Andy Ruffell, who runs 5th and Ocean Productions, which has been producing videos for the EDM-themed clubs in Vegas since 2001. “It's all locked up.”

But the shooter's determined effort to knock out a window, accomplished with a hammer-like device, according to authorities, and use of long-range weapons modified for machine-gun-like action, may cause the hotels to re-evaluate the pools’ safety. The Flamingo overlooks the party pool at Drai’s, for example, while MGM’s Wet Republic has one tower of The Signature facing it, which includes some balconies.

The legacy tower at the Hard Rock Hotel and Casino also has balconies, which directly overlook the Rehab pool. Until Sunday the biggest threat was guests occasionally mooning or flashing partygoers, says DJ cb shaw, who was a resident DJ at Rehab for six years. Shaw, who lives in Las Vegas, says he is still in shock and is not looking forward to a gig at an outdoor concert venue this Saturday. “If somebody lit off a firecracker in the middle of the gig, I would be terrified, I would shit in my pants, 'cause everybody is on edge,” he says.

In recent years, these pool parties have become an integral part of the Las Vegas EDM experience and are a big reason why, beginning around 2010, the city emerged as a formidable competitor to Ibiza. The pool events pull in tens of millions of dollars in revenue for hotels, mainly through cabana rentals that cost upwards of $15,000 and bottle service packages that can exceed $100,000. They also allow DJs to play two gigs a day in the summer -- one during the day and one at night -- making their trips to Vegas more lucrative, says Lars Schlichting, a senior product planning manager with Pioneer DJ, who has frequent contact with top-level DJs: “They are a big reason why there is so much top talent in Las Vegas every weekend.”

The attack in Vegas came as clubs are preparing to begin wrapping up their pool seasons later this month. Some big-name DJs, such as Tiësto and Kaskade, have already declared the end of their summer pool runs. Despite the nervousness of some performers, clubs have not said they are canceling any events, and several clubs contacted by Billboard declined to discuss potential security concerns related to the parties. A spokeswoman for TAO Group said Marquee Dayclub and TAO Beach would host pool parties this weekend as scheduled.

“In Europe, you always think about bombers or people coming into the room and shooting people up close,” says Roman Rosati, a French DJ who lives in Las Vegas and spins at pool parties at Drai’s and the Palazzo. “I have never thought that someone could do something like that from so far away -- we never thought it was possible. This is a new kind of threat.”