URBANA, Ill. (WLS) -- The man charged in the kidnapping of a University of Illinois student was a former student at the Champaign school.
Three weeks after her disappearance, Yingying Zhang's body has not been found.
In a criminal complaint filed Friday, federal investigators said they believe Zhang - a 26-year-old Chinese scholar -- is no longer alive. She had only arrived in the United States a couple months ago with the dream of becoming a college professor.
Just last week, Zhang's father, aunt and boyfriend were in Chicago for a vigil holding out hope that she was still alive.
"The entire family is very, very devastated," said Dr. Kim Tee.
On Friday, kidnapping charges were filed against Brendt Christensen, a 27-year-old Champaign man and former physics PhD candidate at the University of Illinois.
"Those that knew him are quite surprised. There was no hint of something like this," said Prof. Lance Cooper, of the University of Illinois.
The federal complaint states that Christensen had been under surveillance for nearly two weeks before his arrest. A forensic search of his phone revealing visits to a web forum called "Abduction 101," including the sub-threads "perfect abduction fantasy" and "planning a kidnapping."
On June 29, Christensen was captured on audio explaining how he kidnapped Zhang, brought her back to his apartment, and held her in his apartment against her will.
Zhang was last seen getting into Christensen's black Saturn Astra on the afternoon of June 9.
"The school should put a safety manual for students coming to the U.S. because it's a totally different culture, totally different," Tee said.
Investigators believe Zhang accepted a ride from a stranger, because she was running late for an appointment to sign a new lease. Urbana-Champaign is one of the most popular U.S colleges for Chinese students, with more than 5600 enrolled there.
Christensen is scheduled to appear in federal court Monday morning.
Man charged in kidnapping of U of I scholar was surveilled before arrest