Negrete was a freshman at the University of California at Los Angeles in 1999. He lived on the sixth floor of Dykstra Hall dormitory on campus. Negrete had been playing a computer game with a friend. The game ended at approximately 4:00 a.m. on December 10, 1999 and he logged off of his computer at that time. Negrete's roommate awoke at 9:00 a.m. and discovered Negrete had disappeared. Authorities believe he left his room between 4:00 a.m. and 9:00 a.m. that day. All of Negrete's personal belongings were left behind in his residence. Search dogs tracked Negrete's scent to Sunset Boulevard and Bellagio Street in Los Angeles, but no other evidence was located. Authorities released a sketch of a possible witness in Negrete's case in 2000. The unidentified Caucasian man was seen inside Dykstra Hall at 4:35 a.m. on December 10. Investigators do not know if the individual is connected to Negrete's case or if he did indeed witness anything, but they would like to question him. He is described as being approximately 35 years old in 1999 and 5'7 to 5'8 tall with a heavy build.