Sunday night, October 1, 2017.
This account is from the Wikipedia entry for this mass shooting event.
A gunman opened fire on a crowd of concertgoers at the Route 91 Harvest music festival on the Las Vegas Strip in Nevada, leaving 58 people dead and 851 injured. Between 10:05 and 10:15 p.m. PDT, the shooter fired more than 1,100 rounds from his suite on the 32nd floor of the nearby Mandalay Bay hotel. About an hour after he fired his last shot into the crowd, he was found dead in his room from a self-inflicted gunshot wound. His motive remains unknown.
24 guns in total, including:
14 .223-caliber AR-15-type rifles
8 .308-caliber AR-10-type rifles
.308-caliber Ruger American bolt-action rifle
.38-caliber Smith & Wesson Model 342 AirLite TI revolver
I believe all were purchased legally.
After the shooter used a hammer to break two of the windows in both of his suites at the hotel, he began shooting through them at 10:05 p.m. He ultimately fired more than 1,100 rifle rounds approximately 490 yards (450 m) into the music festival audience. He initially started out with a few single gunshots before firing in prolonged bursts. Many people in the crowd initially mistook the gunfire for fireworks. During the shooting, a security fence hindered concertgoers from fleeing the 15-acre concrete lot. The gunfire continued, with some momentary pauses, over the span of ten minutes and ended by 10:15 p.m.
Fifty-eight people were shot to death at the music festival; The Clark County Coroner's Office determined that all 58 victims died as a result of gunshot wounds. Thirty one of the victims were pronounced dead at the scene, while the rest were pronounced dead at hospitals.
An additional 851 people were injured, 422 of them with gunshot wounds. Think about that number.
From a NY Times website:
Denise Salmon Burditus
Thomas Day Jr.
Tara Roe Smith
Kurt Von Tillow
Bill Wolfe Jr.
Remember the victims.