By Steve Beck, Steve Patterson and Elizabeth Hur

PHILADELPHIA (CBS) — Eyewitness News obtained new information on a horrific crash that sent a pedestrian flying off the Walnut Street Bridge after a violent car crash in Philadelphia Tuesday morning.

The crash happened shortly before 10 a.m. at 30th and Walnut Streets in the University City section.

According to investigators, a Mercury Montego was traveling at a high rate of speed when it was hit broadside by a Toyota Camry crossing 30th Street.

At the same time, a 27-year-old male pedestrian was on the sidewalk.

Police say the 43-year-old driver of the Mercury jumped a curb and struck a traffic light, sending the male and the traffic light flying off the Walnut Street Bridge to the road below, about 38 feet.

Eyewitness News spoke to one man, parking attendant Leroy Jackson, who witnessed the whole incident.

“That’s the first time I’ve seen something like that,” Jackson said in disbelief. “That was something.”

Jackson also said he waited with the man until an ambulance arrived.

“He was crying,” he recalled. “And he kept mumbling…I guess, you know, from the pain.”

The pedestrian was rushed to the Hospital of the University of Pennsylvania and is listed in extremely critical condition with body trauma injuries.

The 43-year-old driver of the Mercury was also injured and was also taken to HUP in extremely critical condition but his condition was upgraded to critical by Tuesday night.

The 69-year-old driver of the Toyota was taken to the hospital in stable condition.

We are not releasing any names at police request but we have learned the 27-year-old victim is a grad student at the University of Pennsylvania’s Wharton Business School. We’re told he just moved here and started classes this month and set to graduate in two years.

The crash remains under investigation but we have learned from sources, investigators are looking into the possibility that one of the drivers may have experienced a medical problem, causing the driver to enter Walnut Street just off 30th Street at a high rate of speed and against the flow of traffic.

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