 After a more than six-month investigation, Greenwich police have made an arrest in the case of a woman who was violently robbed of an expensive handbag by a group of four men, leaving her with a brain injury. Police say 23-year-old Zhai Hao Wu of Elmhurst, New York, set up a meeting with the victim last December as she was trying to sell the $130,000 Hermes handbag.