Video provided by witness Edwin Tsigal's Tesla cameras shows the speeding vehicle veering across the center line, striking several cars, launching into the air, and rolling over.
Police said the driver of the overturned Toyota was partially ejected and died at the scene.
"It was horrific," Scott Manning said.
Neighbors and witnesses who spoke to the victim's mother say he was 22 years old.
"His mother pulled up - that was heartwrenching," witness Bonnie Wagner said. "She let out a cry that I'll never forget. She just kept saying he's dead, he's dead."
Manning said he comforted the woman as she cried. "She just started crying on my shoulder and I felt awful," he said.
Police said the driver had been involved in a domestic incident earlier in Lower Southampton Township. Witnesses told ABC affiliate WPVI that his mother said they had argued before he took the car keys and sped off.
"He floored it, and I guess took the anger out on the car and was just driving upset," Wagner said.
Investigators said the driver was heading east on Bristol Road near Chester Avenue when he attempted to pass another vehicle, crossed into oncoming traffic and hit a Hyundai.
The Toyota then went airborne, striking a Honda SUV and an HVAC company truck before landing. The Hyundai ended up in a nearby yard.
The drivers of the Hyundai and the HVAC truck were taken to a hospital.
Witness Bonnie KnollWagner said the man who climbed out of the HVAC truck "was covered in blood."
"It was just horrific, it really was," she said.
Neighbor Deven Harold said he heard "a big boom" and ran outside.
"All I saw was that car flipped over," he said. "Kind of upsetting, not gonna lie, and after hearing the backstory, it's even sadder."
Police have not released the identity of the driver who died. Others involved in the crash told WPVI they were grateful to have survived.