After federal officials announced today that they saw no nexus to international terrorism in the Las Vegas Strip massacre, the Islamic State doubled down with their claim that Stephen Paddock was theirs — even granting the Mesquite, Nev., resident a nom de guerre.

ISIS claimed through their Amaq news agency this morning that the “Las Vegas attacker is a soldier of the Islamic State who carried out the attack in response to calls for targeting coalition countries.” They claimed he had converted to Islam recently.

They issued the claim in various languages, without evidence to back it up.

The special agent in charge of the FBI’s field office in Las Vegas, Aaron Rouse, told reporters, “We have determined, to this point, no connection to an international terrorist group.”

Clark County Sheriff Joe Lombardo said authorities still don’t know the motive of Paddock, 64, who killed himself before SWAT officers accessed his room on the 32nd floor of the Mandalay Bay, a perch he used to unleash automatic weapons fire on an open-air music festival kitty-corner from the hotel.

“We don’t know what his belief system was at this time,” Lombardo said.

Yet ISIS persisted, issuing a longer official communique that called Paddock “Abu Abdul Bar al-Amriki” — the American.

The new statement claims Paddock, specifically answering the call of ISIS caliph Abu Bakr al-Baghdadi, conducted the attack after “accurate monitoring of crusaders” in the venue. It offered no further proof.

The “soldier of the caliphate,” the communique says, “equipped with machine guns and ammunition” fired on the concert with “600 between killed and wounded until the soldier’s ammunition was finished and he became a martyr.”

That reflects the most recent toll from Las Vegas law enforcement of at least 58 dead and 515 wounded.

ISIS has in the past claimed attacks that weren’t found to be linked to the terror group, including the June attack on a Manila casino that left 37 dead. Shooter Jessie Carlos Javier had problems in his personal life including deep gambling debts, and had been banned from casinos before the attack.

Paddock was known as a high-stakes gambler, though his brother said he had no information on whether the shooter was in financial trouble. “We know nothing. If you told me an asteroid fell it would mean the same to me. There’s absolutely no sense, no reason he did this,” Eric Paddock said. “He’s just a guy who played video poker and took cruises and ate burritos at Taco Bell. There’s no political affiliation that we know of. There’s no religious affiliation that we know of.”