The last time anyone saw Samantha Nielsen-Reese, 15, it was Tuesday and she was on the Northwest side.
Nielsen-Reese was reported missing from the area near Montrose and Whipple avenues, according to a missing person alert from Chicago Police.
She has bipolar disorder.
She is described as a 5-foot-2, 193-pound white girl with brown eyes, brown hair and a medium complexion, police said.
Anyone with information about her is asked to contact the Area North Special Victims Unit at (312) 744-8266.