Investigators said it happened near Chester Pike and Pine Street around 2 p.m. The pictured man attacked a woman who was pushing a baby in a stroller, according to authorities.
Multiple bystanders chased the suspect as he fled into a wooded area along the CSX Railroad, but her got away, police said.
The woman was taken to Mercy Fitzgerald Hospital with minor injuries, while her child was unharmed.
Police set up a perimeter and a dog team was dispatched to the area but the suspect was not located, authorities said.
He was described as wearing a blue t-shirt, gray pants, and gray New Balance sneakers. Police said he also had an "obvious deformity to his right ear."
Anyone who can identify him is asked to call the Collingdale Police Department at 610-586-0502. To submit a tip online, visit the Delaware County Crimewatch page.
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