"Again, I offer my thoughts and prayers to the people of the United States. We grieve with the families of the victims.

"We stand with you and we mourn with you in this difficult time. This is a cruel and callous attack on innocent people at a concert."

As political debate erupted in the US over gun laws, Mr Turnbull said his government's Keeping Australians Safe initiative applied to both terrorism and acts of violence with no political motive, such as Melbourne's Bourke Street massacre which involved a killer in a car.

"The focus has got to be on keeping people safe and that applies whether the attacker, the threat, is politically motivated or not."

The crowd fled at the sound of gunshots.



Imagine the deaths if the shooter had a silencer, which the NRA wants to make easier to get. — Hillary Clinton (@HillaryClinton) October 2, 2017

Foreign Minister Julie Bishop, who spent the night liaising with Australia consular officials in the US, says so far, none of the dead or wounded are believed to be Australians.

She said the US would do well to look at Australia's gun laws.

"What we can offer is our experience," Ms Bishop told the Seven Network.


"Under John Howard, we implemented the national firearms agreement - this prohibited semi-automatic and automatic weapons. We had that national gun buyback scheme. We can share our experience.

How long do we let gun violence tear families apart? Enough. Congress & the WH should act now to save lives. There's no excuse for inaction. — Joe Biden (@JoeBiden) October 2, 2017

"But at the end of the day it's going to be up to the United States legislators and law makers, and the United States public, to change the laws to ensure this type of incident doesn't happen again."

More than 11,600 people have died in the US from guns so far in 2017, according to the Gun Violence Archive.

Conservative Republicans have long-resisted tightening gun laws and former Democratic president Barack Obama repeatedly pointed to Australia's conservative Prime Minister John Howard's firearm crack down after the 1996 Port Arthur massacre as a model for the US learn from.

President Donald Trump campaigned during last year's election on a strong pro-gun rights agenda and received the backing of the influential National Rife Association (NRA).

Asked by a reporter on Tuesday if the latest US massacre made the President consider tighter gun laws, such as stricter background checks, a White House spokeswoman said now was a time for mourning and a policy debate might be able to happen later.

"I think one of the things that we don't want to do is try to create laws that won't stop these types of things from happening," press secretary Sarah Sanders said.


"I think if you look to Chicago, where you had over 4,000 victims of gun-related crimes last year, they have the strictest gun laws in the country."

A frustrated former vice president Joe Biden tweeted: " How long do we let gun violence tear families apart? Enough. Congress & the WH [White House] should act now to save lives. There's no excuse for inaction."

Hillary Clinton on Monday slammed Republicans for trying to pass legislation that would overturn restrictions on gun silencers.

"Imagine the deaths if the shooter had a silencer, which the NRA wants to make easier to get," Mrs Clinton tweeted.

"Our grief isn't enough. We can and must put politics aside, stand up to the NRA, and work together to try to stop this from happening again."