A lone gunman released a rapid-fire barrage of bullets on an outdoor country music festival in Las Vegas Sunday night, killing at least 50 people and injuring more than 400 others, police said, in the worst mass shooting in modern American history.From his room on the 32nd floor of a glitzy hotel, the shooter, identified by law enforcement officials as Stephen Craig Paddock, 64, of Mesquite, Nevada, fired shot after shot down on the crowd of about 22,000, sending terrified concertgoers running for their lives.

“We heard what sounded like firecrackers going off. Then all of a sudden we heard what sounded like a machine gun. People started screaming that they were hit… When we started running out, there were probably a couple hundred [people] on the ground,” witness Meghan Kearney told MSNBC.

“People kept dropping and dropping… People were getting shot one foot away from us,” she added. “People were trying to save their friends. There were gunshots everywhere. Helping them would’ve meant that we got shot, too.”

Police responded to reports of the shooting just after 10 p.m. (1 a.m. ET). Las Vegas Metropolitan Police Sheriff Joseph Lombardo told reporters Monday morning that authorities believe Paddock killed himself before police entered his room.

Earlier, officials had said police fatally shot Paddock.

The suspect is believed to have checked into the Mandalay Bay Resort and Casino on Sept. 28, Lombardo said, and had an “excess of ten rifles” in his hotel room.

It was not clear whether Paddock had specifically requested a room on a high floor that overlooked the concert venue or whether he had prevented housekeepers from entering his room in the days prior.

NBC News

The shooting is not believed to be connected to international terrorism. Authorities have not said what kinds of weapons were found.

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