Islamic State has released a new video bragging that the Las Vegas massacre was revenge for US attacks against their caliphate.

In what appears to be a desperate publicity stunt, the terror group claimed the horrific acts of Stephen Paddock, 64, were down to them, saying they radicalised him months before he shot 58 people dead and injured 527 more on Sunday night. He then committed suicide.

FBI officials rubbished the claims, saying he had no affiliation to any terrorist organisations, but the Islamic extremists took to their propaganda news agencies to spread the word.

Paddock (seen here in an undated photo) made a fortune in real estate, his brother said. He seemed an unremarkable man, aside from a heavy gambling habit - and didn't even have a traffic violation on his Nevada criminal record

Photos have emerged of two of the 23 firearms found in Las Vegas shooter Stephen Paddock's hotel room. The weapon on the left has a bump stock added to make it fully automatic, a scope for accuracy and an oversize magazine to hold more ammunition. The weapon on the right has markings indicating it was made by Daniel Defense, a bipod for stability, and a telescopic lens

Stephen Paddock, 64, turned his luxury Las Vegas hotel suite into a sniper's nest on Sunday by smashing open two windows on the hotel's corner and setting up two guns on tripods before opening fire on the Route 91 Harvest music festival below

The latest to emerge is on the pro-ISIS Al-Battar Media Foundation who released a two-minute video in English titled Rightful Revenge, unearthed by the Middle East Media Research Institute (MEMRI).

The video presents excerpts from an eye- witness's testimony about the attack, from statements by the Las Vegas Sheriff, and from an old recording by British ISIS executioner Mohamed Emawzi, who became known as Jihadi John.

In his speech, he says that attacks on Muslims would result in bloodshed in the aggressors' home countries.

A written message appearing on the screen declares that the film is 'a message to America and her allies from the Islamic State,' that 'as you kill us in our country, we will kill you in your country'.

It also shows the scene of the atrocity from above awash with blood with the caption 'we are back because of your arrogant foreign policy towards the Islamic State'.

The video also singles out Donald Trump, insisting the President had ignored their previous 'serious' warnings.

A song, featured regularly in previous Arabic propaganda videos, plays in the background with the lyrics 'Oh, my brothers, jihad is the way, to bring back the honour, the glorious day. The promise of Allah will always remain, the fight for his sake is the ultimate gain'.

Inside the nest: The smashed windows from the suite taken out by Paddock at the Mandalay Hotel in Las Vegas

He lived at the $400,000 property (pictured with crumpled garage door after police raid) with Danley. The home is in a quiet retirement community in which residents must be over 55. Cops found 19 guns there, plus explosives

This was the scene at the music festival before the assassin opened fire on the crowds of 22,000

Debris is strewn through the scene of a mass shooting at a music festival near the Mandalay Bay resort and casino on the Las Vegas Strip, Monday, October 2, 2017, in Las Vegas

Las Vegas police stand guard along the streets outside the the Route 91 Harvest country music festival grounds after a active shooter was reported on October 1, 2017 in Las Vegas, Nevada

Yesterday, the terror group put out a statement claiming shooter Stephen Paddock was a ‘soldier of the Islamic State’.

But the FBI dismissed the claim – saying there was nothing in Paddock’s background to suggest he had become a follower of Isis.

The group, which referred to the Las Vegas attacker by a nom de guerre Abu Abdal-Bar al-Ameriki, has increasingly claimed to be behind a number of attacks, only to later be found to have no link to them at all.

Paddock opened fire on the Route 91 Harvest Festival just after 10pm Sunday night, using a hotel room on the 32nd floor of the Mandalay Bay Hotel and Casino across the street from the festival as his man-made killing nest.

Using 23 rifles and thousands of bullets, he smashed two windows and sprayed bullets down for several minutes at the 22,000 festival-goers down below.

By the time the SWAT team made it to his room, the gunman had killed himself.

The attack is the deadliest mass shooting in modern US history.