The photo of the boy was taken Tuesday by a stranger and shared on Facebook, WCBS-TV, New York, reported.
Police tracked down the person who took the picture, who said he could not get the boy to engage in conversation. The boy in the picture and his mother later visited police to confirm he is not Avonte, CBS New York reported.
Avonte, 14, was last seen on surveillance video leaving Long Island City's Center Boulevard School Oct. 4.
Since his disappearance, police have investigated about 500 leads, but so far none have panned out.
"We've seen a lot of photos turn out to be dead ends and not him," said Avonte's brother Anthony Fontaine.
Avonte, who cannot communicate verbally, was last seen wearing a gray striped shirt, black jeans and black shoes. He is 5-foot-3 and weighs 125 pounds.
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