A Las Vegas Metropolitan police source has confirmed that at least 20 people are dead in a shooting Sunday night outside Mandalay Bay on the Las Vegas Strip.

(RJ) Metro also confirmed about that one suspect is dead on a high-level floor of Mandalay Bay. It’s not known if there are other suspects.

Police are asking people to avoid the area.

Police reported multiple casualties from the incident and possibly two shooters with automatic weapons.

The attack came during the last performances on the final night of the three-day Route 91 Harvest Festival, which has been held for the past four years on an 15-acre lot across Las Vegas Boulevard from Mandalay Bay.

It appeared the shooters were firing down at people from upper-level rooms of Mandalay Bay.

Matt and Robyn Webb from Orange County were watching the final performance of the night at Route 91 when the shooting started and people began to run for the exits.

They said they sheltered underneath their seats as burst after burst of gunfire rained down from the direction of Mandalay Bay.

“It just kept coming,” Robyn Webb said. “It was relentless.”

They eventually evacuated toward Reno Court, where they said they saw as many as 20 people lying in the street bleeding.

“That’s when we knew for sure it was real,” Matt Webb said.

They ended up at Hooters Hotel Casino, but they said they had to flee from there with the panicked crowd as more shots rang out.

“We thought we were safe,” Robyn said.

They ended up sitting together on a curb next to an empty lot on Tropicana just east of Koval Lane, trying to get news on their phones and collect themselves as wailing ambulances streamed to and from the scene.

They said they had no way to get back to their room and their two puppies, now on lockdown at the Delano.

By about 12:45 a.m, five busloads of concertgoers were being taken to the Thomas & Mack Center. About 250-300 people were expected to be taken to the T&M.

Ivetta Saldana said Jason Aldean stopped in the middle of his performance and was rushed off the stage. She was there with a friend and said the shots sounded like fireworks.

She said she hid in a sewer.

“It was was a horror show,” she said standing in Town Square shopping center south of the Strip. “People were standing around, then they hit the floor.”

FBI SWAT as well as SWAT units from Henderson, North Las Vegas and Las Vegas were called to the scene, according to police scanner report.

Multiple ambulances and police vehicles are on the scene, and victims have been sent to University Medical Center and Sunrise Hospital Medical Center. Multiple roads surrounding the area have been shut down.

A reporter on the scene said people could be seen running from a casino entrance into the ground floor of the parking garage at the hotel.

Multiple flights, up to 20, have been diverted from McCarran International Airport as of midnight, according to airport spokeswoman Christine Crews. Limited flights have resumed after airport officials reconfigured flight paths to keep airplanes from getting shot.

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