"If that ramp had been crowded, this would've been a lot worse," Fire Battalion Chief Robert Clark said at the scene.
Just before 6 last night, fire and police officials received reports of a car in the river, near a ramp connecting Chestnut Street to Columbus Boulevard, police said.
When first responders arrived, they found the sedan floating upside down in the river, the driver - its sole occupant - trapped inside, according to Clark.
Witnesses told police that the car sped down the ramp and struck the curb, flipping over as it cleared a 3-foot concrete wall before crashing into the water near the Pier 3 apartments.
Marquita Castleberry, a school-bus driver, said she had just gotten off work and was taking her daily stroll near Penn's Landing, looking for peace and quiet.
She found neither.
"The car just came so fast; smoke was pouring out of it," Castleberry said. "When it hit the water, I just froze and pulled out my phone. I called 9-1-1 and said, 'You gotta send someone, please.' "
Two Good Samaritans and a nearby police officer dived in and tried to save the driver.
One of the bystanders, who lives at Pier 3, was able to grab hold of the driver's arm, according to Clark.
By the time divers from the Police Marine Unit freed the man, he was unconscious and in critical condition, police said.
He was taken to Thomas Jefferson University Hospital, where he was pronounced dead at 7:04 p.m.
A police source said the driver had fled the scene of a crash at 4th and Arch streets minutes before his plunge into the river.
He apparently struck a parked car before speeding away. No injuries were reported.
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