text: The mother of a missing 15-year-old autistic girl has made a desperate plea for help after her daughter disappeared while out walking a week ago. Teenager Kimberly Greenberg became angry and left her Santa Monica home to calm down about 8.30pm on March 24, but never returned. Her mother Janice Greenberg has now made an urgent appeal for help as the teenager, described  as having the mental capacity of an eight-year-old, has gone missing without her cellphone or medication. Kimberly Greenberg, 15, disappeared more than a week ago after going for a walk near her Santa Monica home . The autistic teenager left her home without medication or her cellphone and has not been seen for a week . She told NBC Los Angeles that she adopted Kimberly eight years ago, and the area they lived in was what the teenager considered her 'safe place'. 'It is the worst thing you could ever imagine happening,' she said. 'Absolutely horrific. There's no getting through the day - there's no explaining it. 'I have to keep faith that she's going to come back,' she told KTLA. A LAPD spokesman said Kimberly was last seen wearing a red sweater, jeans and ugg boots when she left home to go for a walk and calm down at the nearby Mar Vista Recreation Centre. Despite knowing the area and walking there often, she has not been seen since. The spokesman said: 'Kimberly is currently taking medication and her family is extremely concerned. She is described as a 15-year-old Hispanic female with brown hair and brown eyes. She stands 4feet, 10inches tall and weights approximately 110pounds.' Anyone with information about her whereabouts should contact the LAPD, Pacific Division Watch Commander at (310) 482-6371. During non-business hours or on weekends, calls should be directed to 1-877-LAPD-24-7 (877-527-3247). Those wishing to remain anonymous can also call Crime Stoppers at 1-800-222-TIPS (800-222-8477).
target: Autistic teenager Kimberly Greenberg went missing more than a week ago .
  The 15-year-old left her LA home to go for a walk and never returned .
  Her mother Janice has now made a desperate plea for help finding her .
  She is said to be very trusting and has the mental capacity of an 8-year-old .