Sun was in charge of product communications at Foxconn, which manufacturers the iPhone for Apple. He was responsible for shipping 16 iPhone prototypes to Apple’s Cupertino, Calif. headquarters. One of those prototypes turned up missing, and Foxconn launched an investigation to find the missing unit. That investigation led to a search of Sun’s apartment, reportedly just prior to his suicide.
Update: An Apple spokesperson has spoken to CNET: “We are saddened by the tragic loss of this young employee, and we are awaiting results of the investigations into his death. We require our suppliers to treat all workers with dignity and respect.”