Ariana Grande has expressed her heartbreak at the mass shooting in Las Vegas that left at least 58 people dead, and called on the world to refer to it as an act of “terrorism”.

More than 500 people were injured at the attack in Las Vegas on Sunday evening, which has since been named as the deadliest mass shooting in US history. Gunman Stephen Paddock opened fire into the crowd at Route 91 Harvest Music Festival near the Mandalay Bay Hotel, and later committed suicide. His motive for the attack has not yet been established.

Writing on Twitter, Grande – who was caught up in a terror attack earlier this year when a suicide bomber detonated an explosive at her concert in Manchester – issued a call for stricter gun laws in the US, and urged her fans to “look at this and call this what it is: terrorism”.

Twenty-two people died and 59 were injured at Grande’s concert at Manchester Arena in May. The attacker was later named as Salman Abedi, a British-born terrorist who appears to have subscribed to radical Islamic beliefs.

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However, many politicians and news outlets in the US have been hesitant to refer to the Las Vegas gunman as a terrorist.

Local police said on Monday that they aren’t treating Paddock’s massacre as an act of terror, despite the fact that Nevada state law defines terrorism as “any act that involves the use or attempted use of sabotage, coercion or violence which is intended to cause great bodily harm or death to the general population” (in which case, Paddock’s actions would appear to fit the bill).

President Donald Trump described the Vegas attack as an “act of pure evil”, but refrained from condemning it as terrorism. Likewise, many US news organisations have avoided using the word terror or terrorism in their reports of the mass shooting.

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Many have argued that this is because Paddock has no proven links to known terrorist organisations. ISIS has reportedly claimed responsibility for the attack, saying that Paddock converted to Islam some months ago. However, there is no evidence to support this assertion, and ISIS has been known to make similar false claims in the past.

In addition, a widely used definition of terrorism cites the importance of there being “political aims” behind an act of mass violence – and at the time of writing, Paddock’s motives remain unclear. He had never faced any “notable criminal charges”, according to CNN, and appears to have purchased his firearms legally.

Paddock’s brother Eric told reporters that he had no knowledge of any mental health problems his brother may have been dealing with. “It’s like an asteroid fell out of the sky,” he said. “If an asteroid fell right here you would feel the exact same way as I feel right now.

“There’s exactly no logic, no reach even for me, where my brother would have done this.”

However, Grande is not the only public figure to challenge people to start referring to Paddock’s actions as terrorism. Rihanna and Lady Gaga also spoke out on the subject, while film director Ava DuVernay cited the language often used to describe white, male mass shooters.

Nevada has some of the least restrictive gun laws in the US. Residents of the state do not need a permit or a license to buy a gun, and they do not need to register how many firearms they have. There is also no limit on the amount of guns any one person can buy at a time.

It is legal to carry an unconcealed firearm in public, and gun owners can bring their weapons to public places including casinos, bars and polling stations.

When police travelled to Paddock’s house after the attack, they reportedly discovered an arsenal of at least 42 guns, explosives and several rounds of ammunition.

Images: Rex Features