'Run, Run As Fast As You Can': At Least 59 Dead, 527 Injured In Las Vegas Mass Shooting [Updated]

[Update: 3:28 p.m.]

The death toll has now climbed to 59, and the count of injuries now stands at 527, reports the New York Times.

The Times also reports that a search of Stephen Paddock's hotel room at the Mandalay Bay uncovered at least 20 rifles, according to authorities. Among the weapons found were AR-15-style assault rifles.

According to a Fox 11 reporter, a search of Paddock's home in Mesquite, Nevada uncovered explosives, 18 firearms, and thousands of rounds of ammo.

Fox 11 also reports that a vigil is planned to take place outside Las Vegas city hall at 5 p.m. on Monday:

[7:40 a.m.]

Authorities say that at least 50 people were killed and 200 injured in a mass shooting at a country music festival on the Las Vegas strip. The shooter had been aiming at the concertgoers from the 32nd floor of his room at the Mandalay Bay hotel, firing bullets from an automatic weapon.

"We heard a couple of pops, then it stopped. Then all of a sudden it started going again, and people started dropping," concertgoer Corinne Lomas told the Las Vegas Sun.

The incident is now the deadliest mass shooting in modern U.S. history. The gunman, identified as Stephen Paddock, 64, died after the police stormed the room. He reportedly shot himself. Police found a cache of weapons in his room.

Country singer Jason Aldean was performing at the Route 91 Harvest fest when the sound of gunfire started just after 10 p.m. PST. Video shows Aldean fleeing the stage:

Some attendees described it sounding like fireworks at first. "I thought it was fireworks going off and maybe it mistriggered, and then it happened again. And when it happened the third time, we knew something was wrong," recalled SiriusXM country radio host Storme Warren.

Videos depict the panicked crowd and the steady gunfire. According to the NY Times, the footage indicated "nine seconds of rapid-fire, continuous bursts, followed by 37 seconds of silence from the weapon amid panicked screaming. The barrage of gunfire then erupted again in at least two more rounds, both shorter than the first."

Festival goers fled the concert grounds, looking for cover. "Everybody's hiding everywhere, they're hiding under the bleachers and the stanchions, anywhere they could and everyone is telling us to 'run, run as fast as you can,'" one attendee told KLAS. "And my husband and I ran out toward our car, and there were people hiding underneath my car for cover and there was a gentleman who was shot and he said, 'Can you help me?' And so I put him in my car and I had like six people in my car, people without shoes, running, just to get away."

Robyn Webb told the Las Vegas Review-Journal the bullets "just kept coming. It was relentless." She and her husband managed to flee, but when they saw around 20 bloody victims, Matt Webb said, "That’s when we knew for sure it was real."

The suspect, Paddock, lived 80 miles from Las Vegas in Mesquite, Nevada, and NBC News reports that he "had been known to local law enforcement." (ISIS claimed to be responsible for the shooting but did not provide evidence.)

His brother, Eric Paddock, expressed shock, "Mars just fell into the earth. We’re completely dumbfounded." He told NBC News that "his brother was retired and was 'just a guy' who went to the hotels, gambled, and went to shows."

A woman, Marilou Danley, who is believed to be either a companion or roommate of Paddock's, was initially sought as a person of interest, but now authorities say she is no longer wanted for questioning. Danley is reportedly out of the country.

Aldean shared a photograph on Instagram, writing, "Tonight has been beyond horrific. I still don't know what to say but wanted to let everyone know that Me and my Crew are safe. My Thoughts and prayers go out to everyone involved tonight. It hurts my heart that this would happen to anyone who was just coming out to enjoy what should have been a fun night. #heartbroken #stopthehate"

Update [9:15 a.m.]: At least 58 people are now confirmed dead and the number of injured is estimated to be at least 515 people, according to Clark County Sheriff Joseph Lombardo's briefing on Monday morning.