'I thought she might have been hit': Vancouver couple survives Las Vegas mass shooting

A Vancouver couple who survived an attack Sunday on a Las Vegas concert that left at least 50 people dead said they felt like "sitting ducks" while hearing bullets ricochet as they fled to escape the seemingly endless rounds of automatic gunfire.

Quinn Mell-Cobb and Madison Milford were uninjured after attending the Route 91 Harvest music festival in an outdoor area known as the Las Vegas Village.

They said they didn't know at first there was a shooting, after hearing a series of "pops" in quick succession.

Mell-Cobb said he initially thought it could have been fireworks, until he saw country singer Jason Aldean run off the stage, the lights come on and a massive rush of people running towards them.

In the initial panic, Milford fell to the ground, but got up and started running after a nearby man told them there were gunshots and they needed to get out of the area.

"At this point I saw her to my right, she fell, and she fell awkwardly and rather quickly so immediately I jumped to the worst conclusion, honestly I thought she might've been hit," said Mell-Cobb.

Milford said they started running towards the bleachers, where they took a sharp left.

• 'Beyond horrific': Shooting on Las Vegas Strip kills at least 50, wounds hundreds

"We heard a ricochet of a bullet when we were under there, which was the most difficult part honestly," she said.

Mell-Cobb said the scene was so chaotic that it was difficult to tell where the gunfire was coming from.

Authorities later found the gunman was shooting into the crowd from a perch on the 32nd floor of hotel across from outdoor venue.

"I said to her, 'We can't stay here. We're sitting ducks here. That guy is shooting at these people.' We couldn't really tell from our vantage point where the shots were coming from, it sounded like it was coming from everywhere," he said.

"What can you say? Really it's not a situation you think you're ever going to be in."

According to Clark County Sheriff Joseph Lombardo, more than 400 people were taken to hospital. It is the deadliest shooting in modern U.S. history.

The gunman has been identified by police as Stephen Paddock, 64, who was later found dead at the Mandalay Bay Hotel and Casino.