But as the afternoon of June 9 wore on, the visiting scholar at the University of IL at Urbana-Champaign kept falling behind as she used city buses to get to her appointment.
Federal Bureau of Investigation agents on Friday arrested Brendt Christensen, 27, for allegedly kidnapping Zhang, but authorities have yet to find her body, and they have not filed a murder charge.
The FBI says Christensen was driving the black Saturn Astra that was captured on security camera video picking up Zhang the afternoon of June 9. Christensen is the car's registered owner, according to a court affidavit. Authorities say they believe she is dead, though her body hasn't been found.
According to the federal charging document, Christensen in April visited via his smartphone two sub-threads entitled "perfect abduction fantasy" and "planning a kidnapping". She had been doing research on crop photosynthesis, which included using drones to study fields.More news: Fabulous Federer trounces Zverev to claim ninth Halle title
Twenty-eight-year-old Brendt Allen Christensen of Champaign, Illinois, was charged Friday and is in federal custody pending a Monday court appearance.
It was reported that agents overheard Christensen saying he kidnapped Yingying Zhang while he was under surveillance on Thursday, according to a criminal complaint.
"They have made an arrest, and now it is time for us as a university community to come together in support of her family and friends in this hard time of loss", he said. Zhang is presumed dead, according to a press release from the Department of Justice. He said he dropped her off a few blocks away. She went missing just weeks following her arrival at the university's Urbana-Champaign campus from China in order to pursue a course in agriculture sciences.
Zhang was last seen June 9.More news: Brazil leader defiant in face of possible charges
Yingying Zhang came to this country with one goal - to further her education, so she could take care of her family back in China.
"There are many ways in which we find out there are problems with students", Cooper said.
There are more than 300,000 Chinese students attending schools in the USA, and Zhang's disappearance and now suspected death, has triggered widespread concern in China. Zhang had a position at the University of IL that would last for a year, "at the university's department of natural resources and environmental sciences". He continued teaching as a graduate assistant and earned his master's degree in mid-May.
"We hope they are wrong, but trust they have creditable information to make this statement", organizers Kim Tee and Randy Tom said in a joint email late Friday night.More news: Shady deal: Trump prepares concessions for Putin at first G20 meeting