The name on that ID is of Dario Gomez-Lopez, 35, of Puebla, Mexico. Police say he is in the country illegally.
However, officers are unsure if that name matches the rape suspect. They said the ID could be an alias, or may not belong to the suspect at all.
At an afternoon news conference, police showed surveillance video of the rapist running from the scene without his pants.
Officers recovered those pants, along with that photo ID.
Police say the attack was interrupted by a passerby who called 911.
The rape happened near the SEPTA station at 8th and Race streets around 9:30 p.m. Sunday.
When they arrived, they found a woman who told the police that a man raped her.
The victim told police she was waiting for a bus when she was dragged between the subway building and a SEPTA truck and raped.
The suspect then fled the scene on foot.
The victim was transported to Jefferson University Hospital.