At least 58 people have been killed and hundreds injured in a mass shooting at a Las Vegas concert.
A gunman, named as 64-year-old Nevada resident Stephen Paddock, opened fire from the 32nd floor of the Mandalay Bay Hotel towards an open-air music festival attended by 22,000.
He killed himself as police stormed the room where 10 guns were found.
Investigators have found no link to international terrorism, despite a claim from so-called Islamic State.
In an address from the White House, President Donald Trump described the attack as “pure evil”.
He praised the efforts of the emergency services, saying their “miraculous” speed saved lives, and announced he would be visiting Las Vegas on Wednesday.
The final shows of the three-day Route 91 country music festival were in full swing when the gunman struck.
Thousands were enjoying a performance by top-billing singer Jason Aldean when the first of several bursts of automatic gunfire rang out – hundreds of shots, witnesses say. That was late on Monday night – 22:08 local time (05:08 GMT on Tuesday).
Hundreds of concert-goers scrambled for cover, flattening themselves against the ground, rushing for the exits or helping others to escape as Paddock sprayed the site from his high vantage point.
“One man had blood all over him and that’s when I knew something was seriously wrong,” Mike Thompson from London, told the BBC.
“People were running and there was chaos.”
Concert-goer Mike McGarry, who survived, told Reuters he lay on top of his children when the shots rang out.
“They’re 20, I’m 53. I lived a good life,” he said.
Many hotels on the Las Vegas strip close to the scene were placed on police lockdown and parts of Las Vegas Boulevard were shut.
Aldean, who was rushed off-stage, shared his reaction on Instagram.
“Tonight has been beyond horrific,” he wrote.
Las Vegas police say the number of people injured stands at 515.
Stephen Paddock, from a community of senior citizens in the small town of Mesquite north-east of Las Vegas, booked into the hotel on 28 September, police say.
His motives for carrying out the deadliest mass shooting in recent US history remain a mystery. Some investigators have suggested psychological issues, but there is no confirmation of this.
His brother, Eric, is dumbfounded that he acted this way.
Las Vegas Sheriff Joe Lombardo described the shooting as a “lone wolf” attack.
“We have no idea what his belief system was,” he said.
So-called Islamic State (IS) has claimed to be behind the attack, saying that Paddock had converted to Islam some months ago.
But the group provided no evidence for this and has made unsubstantiated claims in the past.
FBI Special Agent Aaron Rouse told a news conference: “We have determined at this point no connection to an international terrorist organisation.”
IS’s claim of responsibility for the Las Vegas attack is very unusual in that the perpetrator’s profile does not fit that of supporters or “soldiers” that the group has claimed in the past, writes Mina al-Lami, who monitors jihadist groups for the BBC.
If true, his suicide would be deemed wholly “un-Islamic”, she adds.
Jihadist suicides involve the assailant blowing himself up in order to kill those around him.