CBS Local — U.S. officials are pushing back against the Islamic State of Iraq and Syria’s claims the Las Vegas mass shooting was related to their organization.

According to multiple reports, there is no connection between Islamic State terrorists — or any international terrorist group — and the man who killed at least 58 people and injured more than 500 during a music festival Sunday night.

What We Know About Las Vegas Gunman Stephen Paddock

An FBI official added during a press conference Monday morning that investigators had found, “no connection with an international terrorist group.” The gunman struck from the 32nd floor of the Mandalay Bay Hotel and Casino before reportedly killing himself.

PHOTOS: Terrifying Chaos Of Las Vegas Mass Shooting

ISIS said in a statement that they were responsible for the shooting, carried out by Stephen Paddock, and that the 64-year-old was a, “soldier of Islamic State.” The terror group’s news agency Amaq added that Paddock allegedly converted to Islam months before the attack.

Paddock’s family was reportedly interviewed by the FBI Monday morning at their home in Orlando, Florida. According to his brother, Eric, the frequent gambler had no ties to religion or politics.

“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.”

Police: Shooting On Las Vegas Strip Kills At Least 58, Wounds More Than 500

“We have absolutely no idea how in the world Steve did this,” another relative of Paddock said. Neighbors of the alleged shooter had a different view of him, adding that the 64-year-old was reclusive and would disappear for days at a time to go gambling.

“He was weird. Kept to himself,” one neighbor claimed.

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