Friends of 14-year-old Kelli O'Laughlin held a vigil Friday night as police searched for clues that will lead them toward her killer.
Indian Head Park police believe O'Laughlin may have walked into a burglary before she was killed, on Thursday.
She was apparently stabbed to death between 4:45 p.m. and 5:30 p.m. in her home in the 6300 block of Keokuk Road, east of Interstate 294 and south of Plainfield Road, police said.
O'Laughlin's mother discovered her around 5:30 p.m., police said. O'Laughlin had stab wounds and was pronounced dead at a local hospital.
Police are circulating flyers with the suspect's description, a black man between 5-8 or 5-9, 25-35 years old with a medium build and wearing a dark hoodie.
Investigators are asking pawn shop owners to keep an eye out for coins that were taken from the scene.
Indian Head Park was the scene of several home break-ins over the summer, and someone may have been inside O'Laughlin's house when she arrived home from school.
Parents from Lyons Township High School received an email Thursday night notifying them of the death of the freshman tennis player.
Police Friday morning guarded the entrance to the Indian Head Park subdivision and asked residents for an ID card as proof of their address, and later in the day, stopped cars and passed out the flyer.
Lyons Township High School was offering counseling at the school Friday for students and faculty.
"She was always nice to everybody. Sweet. She wasn't mean to anyone," said Cole Gilchris, a classmate.
A vigil was scheduled for Friday night.
An anonymous donor put up a $10,000 reward for any info that leads to an arrest and conviction in the case.