Police say the bus driver contacted authorities after hearing reports of the hit-and-run.
Investigators say the bus driver told police she thought she hit a bag of trash.
So far, no charges have been filed but the investigation continues.
Witnesses previously said it looked like the victim was hit by a school bus.
The woman killed was identified as Shirley Wilhelm, 78, of the 1000 block of Terrance Lane in Pottstown.
The incident happened around 7:30 a.m. at the intersection of North Charlotte Street and Mervine Street.
Wilhelm was out for her daily morning walk when she was hit.
Friends and neighbors were stunned to hear the news.
"Every morning she would walk about five or six miles. Every day," said Douglas Diener.
Across the street from the scene of the accident is the convenience store where Wilhelm would regularly buy her lottery tickets.
The owner of the store, Sukhjinder Singh, says one of his customers came in to alert him that someone had been hit at the intersection.
Singh tells us, "We tried to shake the lady, but she was dead on the spot. It was very sad."
Singh said surveillance cameras at his store captured the impact. Police are now using that video to track down the driver.
Wilhelm was an active member of St. Paul's United Church of Christ. Friends say she was a pillar of the church and the community and was very involved in food drives.
"Collected food and collected cans and everything. Just a nice lady," said neighbor Jose Rosado.
Adamino Ortiz would often give Mrs. Wilhelm vegetables from his garden. He says she will be missed by everyone.
"The whole neighborhood, because everyone in this neighborhood loved her. It's a big loss," he said.
Wilhelm's family says they have no comment at this time.