A video shared on social media shows the moment gunfire was heard during the concert.

Singer Jason Aldean was performing at the time and quickly left the stage.

The Las Vegas attack tops the list of the most deadly mass shootings in recent US history.

The preliminary number of injured people, more than 200, is significantly higher than previous shootings.

Las Vegas police say two officers were injured in the shooting.

Earlier they said one officer was in a critical condition, but they are now stable following surgery.

The other officer sustained minor injuries.

Eyewitness accounts from those caught up in the shooting have been coming in throughout the day.

Mike Thompson from London says he ran for safety when he heard gunshots.

"We were walking back to our hotel - the MGM - after dinner and we saw people running towards us in total panic.

"One man had blood all over him and that's when I knew something was seriously wrong.

"I could hear automatic gunfire so I grabbed my partner and we ran to the backstreets."

You can read more eyewitness accounts here.

Image source, Getty Images

Police have shared this number to call if you are looking to find missing people.

The BBC's James Cook has arrived in Las Vegas and says the city is "in lockdown".

Logan Cruz and Liberty Psesser were near the stage when the gunman struck.

They told the BBC of the "crazy" scene as people tried to flee the attack.

US President Donald Trump has expressed his condolences.

With more than 50 dead, this is the deadliest mass shooting in recent US history.

It surpasses last year's shooting in a Florida nightclub which killed 49 people and injured dozens.

Image source, Getty Images

George French from Bristol travelled to Las Vegas for the concert. He was near the front when he heard the shots.

Speaking to the BBC, he said: “Everyone ducked down except me, and then I saw people start to stampede, so I got down too.

"We were ushered to a safe place and are still in lockdown in the Mandalay Bay. I was separated from my friends but I’ve spoken to them and they’re all OK.”

Image source, Getty Images

Amy Santos was heading into the Mandalay Room in Las Vegas when she heard what she thought were firecrackers. She describes what happened next.

Las Vegas Police say they have located the two vehicles they were looking for as well as the female person of interest.

The woman is Marilou Danley, who police say was travelling with the gunman before the attack.

Police say two off-duty police officers died in the attack.

Several officers were attending the outdoor Route 91 Harvest Music Festival on Sunday when the gunman opened fire, they said.

In a press conference earlier, Sheriff Lombardo said two on-duty police officers had been injured, one critically.

Image source, Getty Images

Police have named the gunman as 64-year-old Stephen Paddock.

They said he was local to Las Vegas.

Sheriff Joe Lombardo says 50 people died in the attack and at least 200 have been injured.

The gunman is reported to have shot at the crowd from the 32nd floor of the Mandalay Bay Hotel.

The hotel has released this statement:

Didier Perez from Texas described what he saw: “We were leaving a magic show and approaching the Excalibur hotel when we saw people crying and hugging each other near Mandalay Bay.

“We asked one person what had happened, they said they were at a country music concert and there was a shooter.

“Then I saw some people with blood on them. People were in shock and they were crying.

“People were running into the hotel as rumours circulated that there were other shooters but that was a false alarm. It didn’t stop the hysteria though. There was mass panic."

He added: “We were in the casino lobby when the police showed up trying to secure the area.

"We are staying in an Airbnb, but we've been told we can stay in the hotel tonight. We have been moved to the third floor conference rooms and are being given blankets so we can sleep here."

If you're just joining us, here's what we know so far about the mass shooting in Las Vegas.

• Police say at least 20 people are dead and more than 100 are injured after a gunman shot at a crowd of people attending a music festival late on Sunday night.
• The gunman, who fired from the 32nd floor of the Mandalay Bay Hotel on the Las Vegas strip, was shot and killed by police.
• Witnesses say hundreds of shots were fired and the sound of automatic gunfire was heard.
• Police are trying to locate an Asian female named as Marilou Danley who they say was travelling with the gunman before the shooting.
• Sheriff Joe Lombardo said it was a "lone wolf" style attack.
• Police say reports of other incidents at different locations along the Las Vegas strip are false.