It happened on Friday, December 23, at 9:30 a.m.
Police say the 15-year-old boy was on the subway platform at the 53rd Street and 4th Avenue station in Sunset Park when he threw an empty bag of chips on the platform.
The suspect, dressed in civilian attire, approached the boy, showed him what he described as a police shied and told him victim to come with him.
The boy complied and followed the suspect to the white van, where he got in.
He was driven to 92nd Street and Dahlgren Place, where he was allegedly sexually assaulted.
The suspect then drove the victim to 38th Street and 4th Avenue and let him go.
The suspect is described as a white man, age 45 to 49 years old, 5-foot-8 and weighing 145 pounds.
He has a bald head, gray mustache and a mole under the left side of his lip.
Anyone with information in regards to this sexual assault is asked to call the NYPD's Crime Stoppers Hotline at 800-577-TIPS.
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