The target of the pursuit, 20-year-old Dejuan Robinson, managed to get off the highway, but he crashed into another vehicle and a SEPTA bus in South Philadelphia.
Robinson fled on foot and remains at large.
The pursuit began in Wilmington, Delaware, and police from that city were involved in the chase.
The crash left a Wilmington Police SUV on its roof, and a Pennsylvania State Police car damaged. Several passenger vehicles were also involved.
Our sister station WPVI-TV learned Thursday that a three-year-old boy was inside one of those vehicles. He is now hospitalized with multiple injuries.
Megan Stone Kirts, the boy's mother, was driving.
"Next minute I know, five to six cop cars start pounding on my car," she said.
Stone Kirts said she didn't see the vehicles and didn't hear any sirens.
"All of a sudden, you hear a big thump. I see my kid going flying through the air, so I grabbed him," Stone Kirts said.
Her son, David, was strapped into a child safety seat at the time. He is being treated a Children's Hospital of Philadelphia.
"He has a spinal injury, a brain injury, brain bleed, five to six fractured skull marks and other injuries to his body," Stone Kirts said.
Her family has just left breakfast at a nearby Denny's, and they were traveling up I-95 from Maryland to New York.
Her son wasn't the only one hurt. Stone Kirts said her husband suffered six broken ribs, a concussion and a traumatic brain injury.
Robinson is a person of interest in homicide cases and is wanted for probation violations stemming from weapons charges.
With the manhunt for Robinson ongoing, Stone Kirts is left with a number of questions.
"They're telling me that I have to go to the driver of the vehicle for insurance for everything. So I'm like, 'If this guy is wanted, who's not to say the car is stolen, so how am I going to afford this?'" she said.
At least two Wilmington police cars were involved in the crash and five officers were injured. All have been treated and released.
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