Investigators say he robbed and sexually assaulted a 23-year-old woman near Decatur Street in the Brownsville section early Sunday morning.
The man grabbed the victim by the neck, stole her money and attacked her.
The suspect is described as a black male, age 20-26, 5'6"-5'9", with a thin mustache, and was wearing a dark colored jacket, and blue sneakers.
Anyone with information is asked to call Crime Stoppers at (800) 577-TIPS (8477).
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