The man who is accused of kidnapping Yingying Zhang attended a vigil for her the day before he was arrested in the case, authorities said.
Suspect Brendt Christensen can be seen in a photograph taken by CNN's Kaylee Hartung.
He is leaning against a railing behind hundreds of students and community members who gathered to support her on Thursday on the campus where she was last seen. Christensen was arrested Friday and has been charged with kidnapping. Zhang is still missing.
Christensen has been charged but not tried or convicted in the case.
But if -- as authorities claim -- he is her kidnapper, why would Christensen attend a vigil for his victim? In fact, that would not be so unusual. There is no shortage of examples of people who were found guilty of heinous crimes behaving in very a similar manner.
"In a sick, twisted way, some of these criminals will go to the scene of funerals, they'll go to wakes, they'll actually show up," retired police officer Steve Rogers told Brooke Baldwin on "CNN Newsroom."
Rogers is a former Nutley, New Jersey, police detective and was a member of an FBI Joint Terrorism Task Force.
"Sometimes, believe it or not, they are remorseful, they are looking for forgiveness in their own way, and that's why they show up. They're having a hard time coping with what they did.
"Or, they're just confirming that -- 'Hey look what I did, and I got all these people gathered in one area to mourn my victim,'" he said.
Pleading for victims
There have been well-documented cases of kidnappers and killers helping in the search for their own victims, attending rallies held for them, or making high-profile appeals for the missing person's safe return.
Investigators said a 17-year-old convicted in the killing of a 6-year-old
girl in Washington state attended a community vigil for the little girl.
The case of Cleveland kidnapper Ariel Castro
, who pleaded guilty to kidnapping and raping three young women he held prisoner for years, is another example.
One of his victims, Gina DeJesus, was the best friend of his daughter.
Castro seemed shaken by DeJesus' 2004 disappearance, even handing out fliers with the girl's photos. Castro later killed himself in prison.
In 1994, South Carolina's Susan Smith
confessed that she had strapped her two small children into their car seats and pushed the car into a lake. For weeks before that confession, Smith had said she had been carjacked by a black man while stopped at a red light in Union City. During the manhunt that followed, Smith made several TV appearances and tearfully pleaded for the return of her children. She was convicted of murder and sentenced to life in prison.
Attorney: There's a long road ahead
Twenty-six-year-old Zhang had come to the United States from China to further her education. She had been in the United States for only about two months when she disappeared June 9 from the campus of the University of Illinois at Urbana-Champaign, authorities said.
Christensen appeared in a magistrate's court for an arraignment hearing Monday, where he did not enter a plea. He has been charged with kidnapping, and if convicted, the penalty is up to life in prison, said Sharon Paul, spokeswoman for the US Attorney's Office.
Christensen's attorney, Evan Bruno, urged the public to avoid jumping to conclusions.
"There's a long road ahead," Bruno said. "I encourage everyone to be patient, to keep an open mind and wait until the evidence comes in," Bruno said.
Christensen will face another hearing Wednesday to determine whether he should remain in custody, according to the US attorney's office.