Son Went Missing on Father's Day - help sought

This poster appeared up and down 5th Avenue (and probably in other areas) this morning. Being the suspicious person that I am, I always wonder if this sort of thing could be a prank. However, this one seems sincere. The poster basically says that a 20 year-old son has been missing since last Sunday. No name or physical description is given. Any information about his whereabouts would be appreciated by the family: 1 718 998 3152