"The FBI is investigating allegations of criminal acts surrounding the incident at Scottsdale Fashion Square in May 2020," the bureau said in a statement, adding that a search warrant was also executed in Las Vegas, but no arrests were immediately planned. No other details were disclosed.
AIR7 HD was over the scene as multiple firearms that were scattered across the Calabasas property, including a long gun propped up against a hot tub in the backyard, were confiscated by authorities.
Paul was not at home at the time of the raid, according to his attorney.
In early June, misdemeanor charges were filed against Paul following a riot at the mall outside Phoenix. Paul said he was merely trying to find people protesting against the death of George Floyd.
EXCLUSIVE VIDEO: AIR7 HD captures FBI seizing multiple guns at Jake Paul's home
The Scottsdale Police Department said Paul was identified as a participant in the riot at the location and was charged with criminal trespass and unlawful assembly.
Paul denied looting and said he wanted to "share our experience and bring more attention to the anger felt in every neighborhood we traveled through."
In a news release Wednesday, Scottsdale police said those local charges had been dismissed.
"It has been decided that in the cases charging Jake Paul, Arman Izadi and Andrew Leon it is in the best interest of the community to dismiss misdemeanor charges without prejudice so that a federal criminal investigation can be completed," the police statement said, referring to Paul and two others who had been charged in the case.
Video of Jake Paul's house party in Calabasas draws backlash from mayor
Wednesday's search comes about two weeks after Paul hosted a raucous party at the Calabasas mansion, sparking backlash due to the lack of masks and social distancing among the dozens of guests.
Mayor Alicia Weintraub expressed outrage over the large party, which took place despite rising coronavirus cases, hospitalizations and deaths in California.
Videos of the house party went viral on social media, where Paul himself has some 20 million followers.
Weintraub said she learned of the party when residents complained, telling her they saw "tons of people walking on the street unmasked and then gathering."
"I was very upset that somebody would hold such an outrageous gathering in our community," the mayor told ABC News, noting that the city had recently enacted a policy of issuing a minimum-$100 fine for not wearing a facial covering in public. "We're trying to do everything we can to get our numbers down and keep our community safe, and something like this just does the opposite."
The Associated Press contributed to this report.
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