The Dodge Charger had reportedly been parked on the 2000 block of Bambrey Street since sometime over the weekend.
A neighbor alerted authorities after noticing the smell coming from the vehicle. Officers arrived just after 9 p.m. and identified the car as stolen from Southwest Philadelphia.
"I know last night I saw two police cars in front, but I wasn't sure what was," said Nadya Tirado, a neighbor. "I didn't know they found a body right in front of my house."
According to Chief Inspector Scott Small, the Philadelphia Fire Department forced open the trunk.
"That's when they found a body wrapped so you could not see male, female, age," Small said.
Detectives are reviewing surveillance footage from nearby real-time crime cameras to determine when the vehicle was left on the block.
Police say the car was reported stolen on Friday. One neighbor said she first noticed the car on Sunday but did not detect any odor at the time. The trunk was facing the window of another residence.
"There's a lot of kids that play out here," said a neighbor identified only as Ny. "They probably got a whiff of it too, probably why she reported it."
Investigators are also reviewing missing persons reports as they work to identify the victim. No arrests have been made.
Anyone with information can call or text Philadelphia police at 215-686-TIPS (8477) or submit an anonymous tip online.
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