At least 59 people are dead and a further 527 are hurt after a shooting at a country music festival in Las Vegas.
Police have named the gunman as 64-year-old Stephen Paddock, a retired accountant.
The tragedy is the deadliest mass shooting in modern US history.
11:40am Victims fund breaks $2 million
The GoFundMe page dedicated to helping the victims and families of the shooting has broken USD 2 million.
The fundraiser has been up for less than 12 hours and has had over 25,000 people make donations.
The page earlier revised its USD 2 million target to a USD 2.5 million target.
Donations as high as USD 50,000 have come in with most of those donators choosing to remain anonymous.
11:11am Prime Minister Turnbull reflects on attack
Prime Minister Malcolm Turnbull has spoken on the shooting in Las Vegas offering his sincere condolences.
11:02am Australians looking for friends relatives urged to call DFAT
Any Australians who hold concern for and can't contact loved ones in Las Vegas should call the Department of Foreign Affairs Trade on 1300 555 135 (or, if overseas, call +61 2 6261 3305).
10:02am US House of Representative pays respects to victims
The US House of Representatives has observed a moment of silence for the victims of the Las Vegas shooting.
Democratic Party member Katherine Clark stepped out of the House chamber during the silence in protest. She is an advocate for stronger gun control.
10:38am on 3 Oct 2017 Donations to victims fund closes in on $2 million
A GoFundMe page set up to provide relief and financial assistant to the victims and families of the shooting is closing in on its goal of USD 2 million.
The page is reporting that it has raised just under USD 1.8 million in ten hours.
The fundraiser was started by Steve Sisolak, Chairman of the Clark County Commission.
9:44am Shooter's Australian partner: Who is Marilou Danley?
The Australian partner of Las Vegas shooter Stephen Paddock, Marilou Danley was named as a person of interest in the shooting.
Here's everything we know about the Queenslander - Las Vegas mass shooting: Who is Marilou Danley?
9:34am UFC to donate $1 million to families
President of the Ultimate Fighting Championship, Dana White has told a reporter that the organisation will donate USD 1 million to the families of those affected by the Las Vegas shooting.
9:26am Turnbull speaks out on Las Vegas shooting
Prime Minister Malcolm Turnbull has said the Las Vegas shooting is a reminder there is no place for "set and forget" in Australia's national security.
"This is a reminder that we must constantly work to stay ahead of the -- threat, whatever the motives of threat, whatever the motives of those who seek to do us harm," he said in Sydney on Tuesday.
Mr Turnbull praised former prime minister John Howard for bringing in some of the strictest gun laws in the world in the wake of the Port Arthur massacre, which left 35 dead in Tasmania in 1996.
"And we remain ever vigilant to maintain them," he said.
"Another national gun amnesty has just concluded, and in the first two months, over 25,000 weapons were handed in."
Mr Turnbull said he would be convening a special summit of state and territory leaders this week to discuss how to further strengthen and harmonise against the threat of terrorism.
"Again, I offer my thoughts and prayers to the people of the United States," he said.
"We grieve with the families of the victims."
9:13am UPDATE: 59 people confirmed dead
The Las Vegas Metropolitan Police Department have confirmed that the death toll in the Las Vegas shooting has risen to 59 people.
The department also confirmed that 527 had been injured in the shooting with a range of injuries reported including trample and gunshot wounds.
The Sheriff said that as well as multiple firearms found in the shooter's hotel room, 18 additional firearms and explosives had been found at a house in Mesquite, Nevada.
8:53am Shooter played high stakes poker
The Washington Post is reporting that shooter Stephen Paddock was a high-stakes poker player, often gambling tens of thousands of dollars.
Paddock was reportedly living in a quiet town outside Las Vegas, living out his retirement as a high-stakes gambler.
Paddock would frequent casinos with his girlfriend with neighbours reporting he would disappear for days at a time.
The shooter's brother Eric Paddock said that his brother would send him messages telling him about his big wins.
"My brother is not like you and me. He plays high-stakes video poker," he said. "He sends me a text that says he won $250,000 at the casino."
8:14am Niece of shooter speaks out
The niece of shooter Stephen Paddock has spoken out against her uncle and expressed her sympathies to those affected by the massacre.
Nicole Paddock says she did not know much about her uncle but that she would occasionally visit him in Las Vegas.
7:43am Julie Bishop says none of the victims were Australian
Foreign Minister Julie Bishop has confirmed no Australians have been found among the dead or injured in Las Vegas at this stage.
Ms Bishop stressed the situation was still very fluid and she would be updated if any Australians were found to have been involved in the attack at the Mandalay Casino.
"I have been in contact throughout the night," she said on Tuesday.
"The consul general has confirmed there are no Australian victims but we are still making inquiries."
From Perth, Ms Bishop said she had been in contact with Secretary of State Rex Tillerson to extend Australia's condolences to her US counterpart.
7:22am 19 rifles found in hotel room
US news outlet ABC News reported that up to 19 rifles had been found in the hotel room where Stephen Paddock carried out the attack.
Sources close to the investigation revealed that there was a combination of rifles and handguns found at the scene, along with hundreds of rounds of ammunition.
7:11am Local hospitals overwhelmed by casualties
A report in The New York Times report has highlighted the overwhelming numbers arriving at Las Vegas hospitals.
The University Medical Center of Southern Nevada had received more than 100 patients, forcing them to transfer some patients to other nearby hospitals with fewer capabilities.
Many of those working during the day shift remained at the hospital to work on the night shift.
Clinical supervisor Toni Mullan said that the hospital resembled a disaster zone.
"If a nonmedical person were to be sitting there watching this, they would think nothing was being accomplished," she said.
Some hospitals said that they were running out of supplies including IV tubing and fluids, blood pressure cuffs and blankets.
7am: Brother of shooter baffled by attack
The brother of shooter Stephen Paddock has spoken to media saying he cannot make any sense of his brother's actions.
"We know nothing. If you told me an asteroid fell it would mean the same to me. There's absolutely no sense, no reason he did this," said Eric Paddock.
"He's just a guy who played video poker and took cruises and ate burritos at Taco Bell. There's no political affiliation that we know of. There's no religious affiliation that we know of."
6.51am FBI deny ISIS is responsible:
The FBI have said there is no indication shooter Stephen Paddock had any links to foreign terror groups despite ISIS claiming responsibility for the attack.
The Islamic State news agency A'maq said that the attacker had carried out the attack after converting to Islam a few months ago.
"Las Vegas attacker is a soldier of the Islamic State who carried out the attack in response to calls for targeting coalition nations."
In a brief statement, the FBI said they had "determined to this point no connection of an international terrorist group".
6,41am Nancy Pelosi to House speaker Paul Ryan: 'Help end this crisis':
House Minority Leader Nancy Pelosi has urged House Speaker Paul Ryan to create a committee to study legislation that could stop attacks like this happening in the future.
"I urge you to create a Select Committee on Gun Violence to study and report back common sense legislation to help end this crisis," said Pelosi.
"The bipartisan committee would make recommendations to prevent unspeakable tragedies such as the mass shooting in Las Vegas and to restore confidence in the safety of our communities."
Another bill introduced by Republican Mike Thompson in May had also called for the creation of a House Select Committee to study the causes of mass shootings.
6:29am Off-duty police officer identified as victim:
An off-duty Las Vegas police officer was among those killed during the shooting according to Las Vegas police.
The police department said that the officer's name was being withheld until their next-of-kin could be notified.
6:21am Traces being conducted on firearms used in shooting:
The Federal Bureau of Alcohol, Tobacco and Firearms is tracing origins of the guns. At least 10 firearms were found in Paddock's hotel room. However, his brother has told reporters at his home in Orlando, Florida, that his brother had never owned firearms previously. When Paddock moved to Mesquite a few years ago, he owned a couple of handguns in a safe that he'd never used, the brother said.
6:12am Smoke alarm helped in locating gunman:
According to a report in the Washington Post, a smoke alarm allowed law enforcement to locate the room where Stephen Paddock was shooting from.
Smoke from Paddock's gun had filled his room, setting off the alarm and alerting a SWAT team to his position.
The SWAT team was able to locate Paddock's room, which was located on the 32nd floor of the Mandalay Bay Rest and Casino, in 20 minutes.
The resort has 3,309 rooms and a 135,000 square-foot casino.
5:47am 'Too premature to have gun debate':
White House spokesman Sarah Sanders has become emotional while giving a brief update. She paid tribute to victim Sonny Melton, who died trying to protect his wife, as well as concert-goer Mike McGarry who she said laid on top of a group of young people to stop them from being hit.
"I laid on top of the kids. They're 20. I'm 53. I lived a good life," McGarry said, according to Sanders.
She said it was too premature to have policy debate over gun control.
She said Donald Trump will continue with plans to travel to Puerto Rico on Tuesday, local time, and will visit Las Vegas on Wednesday.
5:06am Australian woman named as gunman's live-in girlfriend
Marilou Danley, an Australian woman who was initially being sought by police in relation to the shooting, has been located in another country.
While she is not believed to be involved in the shooting, Las Vegas Metropolitan Police Department Sheriff Joe Lombardo said they will still be interviewing her when she returns.
Paddock's family said she was his girlfriend and lived with him in Mesquite, Nevada.
4:53am First victim identified:
Festival-goer Sonny Melton, a 29-year-old nurse from West Tennessee, was killed as he tried to shield his wife, Heather, from the gunfire.
"He saved my life. He grabbed me and started running when I felt him get shot in the back," she told local TV station WSMV. "I want everyone to know what a kind-hearted, loving man he was, but at this point, I can barely breathe."
Melton was a registered nurse who worked at the emergency room and ICU at Henry County Medical Center in Tennessee. He also assisted his wife in surgery.
4:31am 'Our grief isn't enough' Hillary Clinton
Hillary Clinton says its time legislators stood up to the National Rifle Association.
4:29am
"Before he opened fire late Sunday, killing at least 58 people at a country music festival on the Las Vegas Strip, the gunman Stephen Paddock was living out his retirement as a high-stakes professional gambler in a quiet town outside Las Vegas," an interesting profile on the gunman in The Washington Post.
4:22am Gabby Giffords and husband Mark Kelly call for gun controls
Former US parliamentarian Gabby Giffords is addressing the media with her husband, astronaut, Mark Kelly. Giffords was shot in the head in 2011.
"Your thoughts and prayers aren't going to stop the next shooting, only action and leadership will do that," said Mr Kelly.
He is blasting Congress for doing absolutely nothing on gun controls and says remarkably, Congress is actually trying to make it easier for gun owners to use silencers.
"We do not have to live this way, here in America we are 25 times more likely to die from gun violence," he said.
"This must stop, my fellow Americans we don't have to accept this as normal."
3:59am Republican governor tells 'political opportunists' you can't 'regulate evil'
The political debate over America's relaxed gun laws is once more in full swing following the country's worst-ever mass shooting, with at least 58 dead.
The Republican Governor of Kentucky Matt Bevins has hit out at "political opportunists" saying the Las Vegas attack shows why stricter gun controls are needed and said "you can't regulate evil."
3:32am Donors flock to blood banks
The call was put out for blood donations and locals in Las Vegas have responded and then some.
Local reporter Justin Emerson says there is a long queue outside one blood bank.