EMBED >More News Videos The FBI has launched an excavation project on the edge of California Polytechnic State University, San Luis Obispo, in hope of finding the remains of a student who vanished more than 20 years ago.

SAN PEDRO, Calif. -- A search warrant has again been served at the Los Angeles County home of a former classmate of Kristin Smart, who went missing nearly 24 years ago when she was a 19-year-old college student, authorities said Wednesday.Paul Flores "continues to be a person of interest in the disappearance of Kristin Smart in 1996," the San Luis Obispo County Sheriff's Department said in a statement.The Los Angeles County Sheriff's Department assisted in serving the search warrant, which remained sealed, the news release said. No other details were immediately disclosed.San Luis Obispo County authorities in February served search warrants at four locations in the states of California and Washington.Smart was last seen returning to her California Polytechnic State University dormitory from an off-campus party on May 25, 1996.