Hillary Clinton has launched a scathing attack on the National Rifle Association - calling for people to stand up to the powerful gun lobbying organisation and demand greater gun control.

In a series of tweets published in the hours after 50 people were killed and more than 400 injured in the Las Vegas shooting, the former Democratic presidential candidate offered her sympathy to those caught up in the massacre and those members of the emergency services scrambling to respond.

Yet she also focussed criticism on the powerful NRA, the most influential gun rights lobbying group in the country which helps fund political candidates across the nation who reject demands for greater gun control.

In addition to demanding the right to bear arms - something they claim is afforded to them in the Second Amendment - the NRA has pushed for scrapping current restrictions that make it more difficult to buy silencers for guns. Among those lending their voices to the campaign are Donald Trump’s eldest son, Donald Trump Jr.

“The crowd fled at the sound of gunshots,” she wrote. “Imagine the deaths if the shooter had a silencer, which the NRA wants to make easier to get.”

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She added: “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.”

The NRA endorsed Mr Trump in last year’s election, an announcement that at the time came at the earliest stage in the political cycle.

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Mr Trump told an NRA gathering: “The Second Amendment is under a threat like never before. Crooked Hillary Clinton is the most anti-gun candidate ever to run for office. And, as I said before, she wants to abolish the Second Amendment. She wants to take your guns away. She wants to abolish it.”

The NRA spent more on the 2016 elections than it had ever done - a a minimum of $36m, according to the Centre for Responsive Politics.

The organisation said Mr Trump was by far the largest beneficiary, with the NRA spending more than $21m to help him: $9.6m on adverts and other pro-Trump materials, and another $12m attacking Ms Clinton.

During the election, the issue of gun rights became a major issue of disagreement between the two candidates. While Mr Trump promoted himself as a staunch defender of gun rights, Ms Clinton said she felt sensible regulations on who was able to buy weapons and the need for background checks, did not break with the idea of the Second Amendment.

Mr Trump’s eldest son has emerged as a leading voice in the campaign to overturn restriction on the sale of silencers, or suppressors.

Restrictions on their sale were first introduced during the administration of Franklin D Roosevelt, and advocates say the sound of a gun being fired acts as a loud, obvious safety signal for people to take cover, run the way other way or simply be alert.

A bill introduced earlier this year by Republican Jeff Duncan, a congressman from South Carolina, seeks to frame the issue as public health matter, saying that gun owners risk suffering hearing damage without access to silencers.

Mr Trump JR paid a visit to a manufacturer of suppressors in Utah, SilencerCo, where he tested its products.

“I love your product,” Mr Trump Jr, a keen hunter, said in a promotional video published by the company.