NEW YORK (WABC) -- A desperate search is underway for a Boston University student who went missing while visiting New York City.25-year-old Zachery Camhi was last seen walking out of the East Side New York hotel on Lexington Avenue one week ago, but friends say they received tips that he was recently seen around Bryant Park.He was diagnosed with bi-polar disorder several years ago, and has gone missing in the past.Several of his friens are flying in to help with the search.Zachery was wearing a burgundy button-down shirt and slacks as seen in the picture attached. He is 5'8" and 160 pounds. He has no cellphone or wallet on him.He is a music student at Boston University and an accomplished classical double bassist. He and his friend, Constantine, were driving to NYC from Boston to pick up Zac's double bass that had been stored at a friend's house for the past 2 weeks.