MADISON — Borough and Drew University police are working with the Morris County Prosecutor’s Office to find a student who has been missing for a week. Friends and relatives are worried because it is unlike the hardworking student to fall off the radar and not respond to messages. Ajay Sah, a 22-year-old junior from Nepal, was last seen on the Madison campus the afternoon of Jan. 19. He was reported missing three days later. Friends have posted on Facebook that the last activity on his credit card was the purchase of a train ticket to New York on Jan. 19. Sah is 5 feet 6 inches, 125 pounds with black hair and black eyes. He was last seen wearing a black leather jacket and a gray hoodie.