By CBSLA Staff

LOS ANGELES (CBSLA) – Authorities Monday morning served a search warrant at the San Luis Obispo County home of the father of a man suspected in the Northern California disappearance of Kristin Smart back in 1996.

Investigators raid a home in Arroyo Grande, Calif., as part of the Kristin Smart investigation. March 15, 2021. (San Luis Obispo County Sheriff’s Office)

Investigators with the San Luis Obispo County Sheriff’s Office raided the home of Ruben Flores in the city of Arroyo Grande at around 7:30 a.m. in the 700 block of White Court. He is the father of 44-year-old Paul Flores, the prime suspect in Smart’s disappearance.

Cadaver dogs and ground penetrating radar are being used in the search, the sheriff’s office said. The warrant authorizing the search has been sealed.

In May of 1996, Kristin Smart of Stockton disappeared while a freshman at California Polytechnic State University in San Luis Obispo. She was last seen leaving an off-campus party. Her body has never been found.

Flores was a fellow student at Cal Poly at the time of Smart’s disappearance and is believed to be the last person to see her alive.

FILE — A man believed to be Paul Flores runs back into his home after the FBI and San Luis Obispo County Sheriff’s Office question him and search his property in San Pedro, Calif., in connection with the disappearance of 19-year-old Kristin Smart. Feb. 5, 2020. (CBS2)

Flores, who resides in San Pedro, was arrested last month on an unrelated weapons charge. He was released on bail.

In February of 2020, and again last April, detectives searched his San Pedro home in connection with the case.