The woman was shoved to the ground about 9:10 p.m. on Monday near Benner Street and Second Avenue, according to Highland Park police.
The man held the assault victim down before fleeing the area, Middlesex County Prosecutor Yolanda Ciccone and Highland Park Police Chief Richard Abrams said on Friday.
The suspect is described as a black male, with black hair, approximately 6 feet tall and about 25 years old, wearing a blue surgical mask and eyeglasses.
No other details were released.
The investigation is active and continuing, Ciccone said.
Police are seeking help from anyone in the area who may have seen the suspect or possesses surveillance video that may help the investigation. Anyone with information is urged to call Highland Park Detective Sean McGraw at 732-572-3800 or Detective Kevin Schroeck of the Middlesex County Prosecutor's Office at 732-745-4194.
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