Police responded to reports of a shooting in the 5000 block of North Fairhill Street around 1:40 p.m. on Wednesday.
When they arrived, police learned that a USPS postal worker was driving near 900 Courtland when he saw a 20-year-old man, who appeared to have a gunshot wound to his stomach, running toward the vehicle.
The wounded man, who police say was armed with a gun, then jumped into the postal worker's vehicle in an effort to get to a hospital.
When the victim jumped in, he allegedly pressed on the gas pedal, causing the postal worker to lose control of the vehicle and crash into a median.
The victim then got out of the postal vehicle and flagged down another car, which took him to Albert Einstein Medical Center, according to police.
The victim is said to be in critical condition.
The postal worker was also taken to Albert Einstein Medical Center after sustaining injuries from the accident.
Investigators said they recovered eight .45 caliber shell casings, seven 9mm shell casings and firearms at the scene.
No one has been arrested and no motive is known at this time.
The investigation is ongoing.