Details of Disappearance
Zheng was last seen in Columbia, Missouri on September 17, 2000. His wife, Xiang Sun, disappeared on September 23, six days later. Zheng was supposed to go visit his daughter, Xiang's stepdaughter, in Iowa City, Iowa, but he never arrived there and his vehicle was later found still at his residence in Missouri. Xiang disappeared on the day he was supposed to return from Iowa.
Zheng was a graduate student at the University of Missouri and his son was also attending the university at the time of his father and stepmother's disappearances. Both Xiang and Zheng are originally from China, and both of them left their passports behind. Few details are available in their cases.