The Islamic State terror group claimed Paddock converted to Islam a few months ago, through its official Amaq news channel.
They said the attack, the deadliest mass shooting in US history, was carried out by a “soldier” of the caliphate and was done “in response to calls to target coalition countries.”
In another statement released hours later, Isil referred to Paddock by the nom de guerre Abu Abd al-Barr al-Amriki and said he answered a call to arms by its leader Abu Bakr al-Baghdadi.
US officials have said they are examining the claim, but are yet to find any evidence linking the shooter to any organised terrorist group.
Relatives described Paddock as “just a guy” who was never in a hurry and retired to the Nevada desert to enjoy a dry climate and Las Vegas’s casinos.
“We can’t understand what happened,” a distraught Eric Paddock, Stephen’s brother, told reporters outside his home in Orlando, Florida.
He said his brother was “not a normal guy” and “played high stakes video poker”. He said his brother being named by authorities as the shooting suspect was “like if an asteroid fell out of the sky”.