SALINAS, Calif. – FBI officials called media reports characterizing the Gilroy festival gunman’s ideology “wrong” after outlets referenced a social media post and literature associated with white supremacists.

Speaking to reporters Wednesday outside the festival grounds – where three were killed and 12 injured Sunday – John Bennett, FBI special agent in charge, said investigators still do not know what the ideology was of the 19-year-old shooter, Santino William Legan.

“We’re looking at multiple threads of conversations that he’s had,” Bennett told reporters, according to footage from KTVU. “However, we’re still not comfortable in saying it’s an ideology, one way or another.”

The FBI agent added officials are awaiting the arrival of the bureau's Behavioral Analysis Unit to come out and better profile and help look at potential mindset and ideology.

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In a press conference Tuesday afternoon, FBI Special Agent in Charge Craig Fair said investigators had no reason to believe the shooter was targeting any particular characteristics Sunday. They were still reviewing his social media and digital media forensics, among other pieces of information.

In an Instagram post just before the shooting, a now-deleted account believed to belong to the gunman urged people to read “Might Is Right,” a late 19th century book that the Southern Poverty Law Center said is “widely popular” among white nationalists, Rolling Stone reported.

The post reportedly went on, “Why overcrowd towns and pave more open space to make room for hordes of mestizos and Silicon Valley white tw*ts?”

Bennett said Wednesday that, just because someone posts about an 1890s book, it’s information anyone can put out.

Gilroy Police Chief Scot Smithee said the shooter used a legally purchased AK-47-variant assault rifle and authorities recovered a shotgun recovered in his car parked near the park. A bag with additional magazines was recovered in the creek, which is believed to be where Legan traversed to get in the park by cutting a fence.

Inside, he killed Stephen Romero, 6, Keyla Salazar, 13, and Trevor Irby, 25, and injured 12 others. Gilroy police fatally shot him in about a minute with handguns.

Bennett has said they are “highly confident” he acted alone. According to video footage viewed before the shooting, the gunman frequented several “big box stores” by himself, Smithee said.

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According to the Associated Press, officials also conducted a search warrant at his northern Nevada apartment. They reportedly found a bulletproof vest, empty shotgun and rifle boxes, a gas mask, empty ammunition boxes, hard drives and other electronic devices.

Smithee said both weapons were bought in Nevada.

In the seizure at the shooter's Nevada home, the San Francisco Chronicle reported officials found reading materials on white supremacy and radical Islam, per an anonymous federal law enforcement source. The reading materials were apparently not included in the items found in the search warrant released Tuesday, according to The Chronicle.

Bennett said those findings of literature are “erroneous and incorrect information,” though he said there were many materials found and they need to be sorted.

“To call it ideology in one way or the other is conflicting readings,” he told reporters. “Just because someone has a book in their house doesn't mean they are leaning one way or another.”

He added officials are not “overly concerned” of items found in the apartment.

They are not ruling anything out at this point in the investigation, though, Bennett said.

Follow Eduardo Cuevas on Twitter: @eduardomcuevas.