Two mass shootings in the United States have left 29 people dead.

Twenty people were killed after a shooter opened fire in a shopping mall in El Paso, Texas on Saturday.

The attack in the predominately Latino city was motivated by white nationalism and anti-immigration rhetoric.

A 21-year-old white man, Patrick Crusius, has been charged over the shooting.

A second attack occurred just 13 hours later in Dayton, Ohio.

Nine people were killed when 24-year-old Connor Betts opened fire in a bar.

His sister was among those killed in the attack.

There have been 251 mass shootings in the US so far this year, more than one per day.

Joseph Siracusa, human security expert at RMIT University, said Australia does a “pretty good job” of preventing shootings, but there is still a risk.

“There are probably white extremist terrorist groups here… we have to assume that there’s a version of it here,” he told 3AW’s Neil Mitchell.

“I think Australians are a little bit ahead of the curve because they’re still pretty shocked when these things happen.

“Americans are shocked, but they’re not surprised.”

Mr Siracusa said “eternal vigilance” is required to prevent shootings.

“What I like about Australia is it spends a lot of time making sure people don’t get the guns, whereas in America they don’t do a thing about stopping them from getting the guns, but they spend days and weeks and months trying to figure out what the motives were,” he said.

“If you can go out and get an assault rifle, and you can start fantasising about who you are on one of these social media channels, which provide echoes … you might do something crazy.”

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