It happened around 9:30 p.m. Tuesday at Tabor Avenue and Landis Street in Crescentville.
Witnesses say the driver's Monte Carlo was heading south on Tabor at a high rate of speed when he lost control and hit a Lexus pushing it right onto the sidewalk into the retaining wall of a house.
People say the driver jumped out of the car, pulled a 3-year-old or 4-year-old child out of the backseat, and took off running with the possibly injured boy or girl.
Police say they've been checking local hospitals and searching the area but so far they have not located the man and that child.
Officers say they found drugs inside the Monte Carlo.