Flores was apprehended in Rancho Palos Verdes on Thursday on suspicion of being a felon in possession of a firearm, according to the Los Angeles Police Department.
The arrest was "a result of information obtained during our search warrants last year at the home of Paul Flores as part of the Kristin Smart investigation," San Luis Obispo County Sheriff's Office said, CBS News reported.
No further details surrounding his arrest were provided by law enforcement.
For years, the 44-year-old San Pedro man has been considered by local authorities to be a person of interest in Smart’s disappearance.
A spokesperson for Smart’s family declined to comment on the gun charges.
“The Smart family has no comment regarding today’s arrest of Paul Flores for illegal gun possession in Southern California,” John Segale said in a statement sent to Oxygen.com.
On May 25, 1996, Kristin Smart, a student at California Polytechnic State University, left an off-campus fraternity party near the school, located in San Luis Obispo. Flores was the last person to see the 19-year-old alive, according to witnesses. Smart was declared legally dead in 2002, though her body has never been discovered. Flores has never officially been charged in her disappearance.
Smart would have turned 44 this month.
Her family have filed a number of civil suits against Flores in the years since Smart's mysterious disappearance, according to the San Luis Obispo Tribune.
Last year, detectives revealed they’d possibly uncovered new evidence in the Smart case.
The San Luis Obispo County Sheriff’s Office “served search warrants for specific items of evidence inside four separate locations in California and Washington,” the agency said in a statement. Flores' residence in Los Angeles was one of four sites where warrants were previously executed. Investigators also seized two of his trucks and electronic equipment from his home.
Investigators were also pursuing DNA evidence and other leads related to Smart’s disappearance, sources told the Los Angeles Times last February.
Flores was previously convicted on drunk driving charges, KSBY reported.
He was booked into a Los Angeles County detention center. Flores posted his $35,000 bond and was released, according to online jail records. His next court date is scheduled for June 6.
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