Police say it happened just before 2 a.m. at Reservoir Drive and Diamond Street.
A severely damaged wheelchair was at the scene when officers arrived, however, police aren't sure if she was in the wheelchair herself or pushing it across the street at the time she was struck.
Officials say people who called 911 told police the woman was initially still alive when they saw her lying in the road, but she was pronounced dead at the scene.
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"We know this female was hit with such force she was launched out of one of her boots that she was wearing, because one is on the highway. And 100 feet away she's lying with another boot on," said Chief Inspector Scott Small with the Philadelphia Police Department. "We're hoping our real-time cameras either recorded the vehicle prior to or after striking this female. We do know at least two people pulled up after the accident and she was semi-conscious."
Small said she appears to possibly be in her 40s.
The striking vehicle is believed to be silver or gray after car parts were found left behind at the scene, police said. They also said they aren't sure which way the driver took off after the crash.
Accident investigators are checking for any surveillance cameras in the area.
Anyone with information is asked to call police.
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