It happened on Sunday, February 21 between 11:30 a.m. to 11:40 a.m., according to police.
Police say the 55-year-old woman was shopping with her husband when she used the bathroom on the third floor. That's when the suspect, who police say was armed with several cooking utensils, jumped over the stall and attacked the woman.
According to investigators, video shows the suspect enter the restroom before the victim, preying on the next person who entered.
"It's pretty brazen to go inside a bathroom for 20 minutes to wait there without thinking someone else is going to go in and find them," said Special Victims Unit Captain Mark Burgmann.
After the assault, police say the suspect fled the scene by taking SEPTA's Market Frankford Line at 13th and Market streets at 11:45 a.m.
Around 11:54 a.m., video shows the accused suspect exiting the SEPTA station at 52nd and Market street.
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The suspect is described as a Black man in his 20s with a thin build. He was last seen wearing a black hoody, black pants with white stripes on the left leg, black sneakers with white around the sole, three quarter length jacket with a hood and white writing on the left shoulder. He was also wearing a surgical mask.
Anyone with any information is asked to call police at 215-685-3252.