LAS VEGAS (KGTV/KTNV) - No charges are expected to be filed against Marilou Danley, the girlfriend of Las Vegas shooter Stephen Paddock, but authorities revealed that a person of "federal interest" is being investigated by the FBI.
Clark County Sheriff Joe Lombardo, the head of the Las Vegas Metropolitan Police Department, said at a Friday press briefing that he "knows and believes" that the only person responsible for the Oct. 1, 2017, mass shooting was Paddock.
He did not further elaborate on the FBI's investigation into the person of interest.
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Lombardo said the briefing was to introduce the police department's preliminary investigative report into the shooting at the Route 91 festival. The report would outline the sequence of events -- starting with Paddoc checking into a downtown Las Vegas hotel on Sept. 17 -- that ultimately led up to the Oct. 1 tragedy.
Lombardo also told the media that investigators reported finding child porn on Paddock's computer and referred to the gunman's search history as "disturbing."
Lombardo said Paddock researched ballistics and SWAT tactics, and also searched for other potential venues to carry out possible attacks.
As for a motive, Lombardo said investigators have not determined why Paddock carried out the shooting. However, Lombardo said one possible motive could involve the gunman's loss of "significant amount of wealth" before the shooting.
Lombardo noted that the gunman did not leave behind a suicide note or manifesto.