There was confusion and panic seconds after Philadelphia police say the two cars collided in the intersection of 18th and Spring Garden streets Wednesday around 4:20 p.m.
The impact sent one of the cars, a silver Nissan Versa, onto the sidewalk where the 79-year-old man was standing with his 77-year-old wife.
"I heard a loud crash and I heard people on the street screaming," witness Erdem Varol said.
People rushed to help the elderly couple.
The man took most of the impact as the car slammed into Highway Tabernacle Church.
He was trapped under the vehicle while witnesses say his wife was partially pinned.
"I saw this car and two people pinned against the concrete wall and I saw the driver coming out of the car and I think she was in shock and she started crying," Varol said.
Firefighters freed the 79-year-old man who died at nearby Hahnemann University Hospital.
Police say he and his wife, who was also transported to the hospital, came down from Blue Bell, Montgomery County to do some shopping.
Investigators say the woman driving the other car, a Toyota Corolla, was traveling north on 18th and the other female driver of the Nissan was heading west toward the Art Museum when someone possibly ran a red light.
"Both vehicles sustained damage to their front end so we're not sure at this time who was to blame, if any, and who ran the red light," Philadelphia Police Chief Inspector Scott Small said.
The pastor of the church, which didn't appear to suffer any damage, says he's praying for the victims.
"It brings home to me again the importance of staying and being right with God and not knowing what tomorrow may bring," Mark Boucher said.
The names of the elderly Montgomery County victims have not been released yet.
The woman is in stable condition tonight.
The two female drivers were checked out at Thomas Jefferson University Hospital; they are expected to be okay.