Authorities released a sketch of the suspect accused of the sexual assault on Wednesday.
They say the man walked up behind a 9-year-old girl in the park on Monday afternoon, near East 75th Street, and then grabbed her buttocks.
Police say the suspect, who was wearing a medical mask, ran away.
The suspect is described as approximately 25 years old, 5'7'' to 5'9'' and about 150 to 160 pounds.
He was last seen wearing a black hooded sweater, black sweatpants and a blue surgical mask.
Anyone with information in regard 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). The public can also submit their tips by logging onto the CrimeStoppers website at WWW.NYPDCRIMESTOPPERS.COM or on Twitter @NYPDTips. All calls are strictly confidential.
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