Investigators say the suspect first offered to carry the 72-year-old's bags for her on Wednesday near East 9th Street and Avenue P in Midwood.
After carrying the woman's bags, the suspect took out a knife and demanded the woman's purse.
When she screamed - the suspect ran off.
The suspect is described as a male, 40 to 50 years of age, with a bald head, last seen wearing a red hooded sweatshirt.
Anyone with information in regards to this incident is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
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