to Dubois ' body after being assured that it would not be used against him in court . Gardner avoided the death penalty with his guilty plea but will be sentenced June 1 to two consecutive life terms without the possibility of parole , under terms of the plea deal with prosecutors . On February 24 , a day before King went missing , an 11-year-old girl reported that she was walking home from school when she heard a vehicle slowly approaching her from behind , according to an affidavit requesting a police search of Gardner 's home , posted on the website of CNN affiliate KTLA-TV . The documents were unsealed Monday , KTLA reported . The girl told police the vehicle drove past her and then parked about 30 feet in front of her , the documents said . The driver stayed in the vehicle , the girl said , and did not attempt to speak to her . But a woman pulled up next to the girl and told her the person in the vehicle `` seemed very suspicious '' and offered to follow her home , according to the affidavit . The man , who was
-LRB- CNN -RRB- -- Authorities believe that a registered sex offender who this month admitted killing two California teenagers attempted to follow an 11-year-old girl walking home from school the day before one of the teens disappeared , according to documents filed in the case . John Albert Gardner , 31 , pleaded guilty April 16 to killing Chelsea King , 17 , and Amber Dubois , 14 . He also pleaded guilty to a charge of assault with intent to commit rape in a December incident involving a third woman . King was last seen leaving Poway High School in suburban San Diego , California , on February 25 . Her car , with her cell phone inside , was found at Rancho Bernardo Community Park . King was known to run on the park 's trails . Her disappearance triggered a massive search that ended a few days later , when King 's remains were found in the park . Dubois disappeared in February 2009 while walking to school in Escondido , California . She was considered a missing person for more than a year until her remains were found in March . Prosecutors said Gardner led police