SCHAUMBURG, Ill. (CBS) — Six days after a Schaumburg High School track star died in a hit-and-run accident, police still had few answers.

the family of 18-year-old Mikias Tibebu was hoping to change that. His father, Tefera Beyene, said during a news conference at Schaumburg Police headquarters Thursday that the family would add $10,000 to the reward being offered for information leading to the motorist.

“Come forward and talk to Schaumburg Police,” he said. “Think of yourself, but put yourself in someone else’s shoes.”

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Schaumburg Police Sgt. John Nebl said detectives have no video of the intersection of Schaumburg Road and Branchwood Drive, where the accident occurred at approximately 12:30 a.m. Saturday. He said police were checking cameras elsewhere along Schaumburg Road to narrow the vehicle search.

The autopsy revealed injuries that appear to indicate that Tibebu was laid out flat on Schaumburg Road when struck, although Nebl said police do not know if he tripped and fell or had other problems.

But as a result, Nebl said it is entirely possible that the motorist did not realize he had struck a person, although it would have been fairly obvious that the car had hit something. The damage to the car is probably far less than it would be had the car struck someone who was standing up, Nebl said.

He said several cars that passed the accident scene moments later stopped to render assistance, including a couple of nurses.

Police have been able to account for Tibebu’s actions for the six hours before the accident, except for the last five minutes, when he apparently excused himself from a group of three friends, about a block from the accident scene. Nebl said that so far, police have not found any evidence of drinking, drugs, a fight or other disagreement.

A memorial service was scheduled 7-9 p.m. Thursday at Schaumburg High School, 1100 W. Schaumburg Rd., in Schaumburg. Principal Tim Little said students, their families, and other members of the community are welcome, and said that Beyene would read a copy of the letter that Tibebu wrote recently to colleges, seeking admission next fall.

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