CHICAGO — Yingying Zhang, the daughter of a working-class factory driver from China, took the same career path as millions of other young Chinese academics before her: She traveled to a university in the U.S. with dreams of one day landing a professorship and being able to help her parents financially.

But just weeks after arriving at the University of Illinois, the 26-year-old visiting scholar in agriculture sciences stepped off a bus on a sunny afternoon and got into a black hatchback. She hasn't been seen since.

Her disappearance June 9 on her way to sign an apartment lease is being treated as a kidnapping. The case has shaken staff and students at Illinois' flagship public school in Urbana-Champaign. And it's led some parents of the more than 300,000 Chinese students currently studying at American universities to question whether it's safe send to their children to the United States.

In this undated handout, Chinese scholar, Yingying Zhang, is shown. University of Illinois Police Department

Zhang's father, Ronggao Zhang, traveled to the university from the family's home in Nanping, China, to await word on his daughter. He had a message for whoever might have abducted her.

"We will forgive you," he said in a telephone interview. "But please, let Yingying go."

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The 53-year-old, speaking through a translator, had a message for his daughter, too: "Yingying, please be strong."

Local police and the FBI say Zhang's case is a top priority, though they have withheld details of their investigation, even from the father, said Yingying Zhang's boyfriend, who sat in on the weekend interview with the father from the 44,000-student campus about 140 miles south of Chicago.

"So you can imagine the anxiety," Xiaolin Hou said. "It's almost torture ... not knowing anything."

Yingying Zhang (L). University of Illinois Police Department

Chinese media have covered Zhang's disappearance, with her friends and acquaintances drawing attention to her case on Chinese social media sites such as WeChat.

"There's so little we can do at home, but we'd like the local police in the United States to stay on top of the case and not to let it slide," said Zhao Kaiyun, a roommate of Zhang's at Peking University Shenzhen Graduate School. Zhang graduated last year with a masters' degree in environmental engineering.

The University of Illinois has the largest Chinese student population of any U.S. college, with 5,600 students enrolled, according to U.S. government data.

By chance, U of I representatives recently held a previously scheduled orientation session in China for students headed to the school and their parents. Several attendees asked about Zhang's disappearance, said Robin Kaler, the associate chancellor for public affairs.

"Parents were very concerned," she said. "We obviously tell them that it is a very safe community in general, but that there are instances when horrible things can happen. And this is one instance."

Urbana-Champaign, with a population around 250,000, typically records no more than a few homicides each year.

The university's reputation as a leader in agriculture studies attracted Zhang to the school. She's been doing researching on crop photosynthesis, Kaler said. The expectation was that she would begin work on her Ph.D. in the fall.

Yingying Zhang University of Illinois Police Department

One central motivation for everything she did was a desire to help her parents in Nanping, a city in a picturesque part of China amid mountain ranges and forests, her boyfriend said. She set aside part of her research income to buy her parents devices to make their lives easier, including a microwave and a cellphone.

He and the father described Yingying as bright and studious, fun-loving and outgoing. She plays the guitar and was the lead singer in band called "Cute Horse" at college in China. One of her favorite songs, her boyfriend said, was "The Rose," a hit in 1980 for American singer Bette Midler.

Yingying, they added, is also street-smart and cautious and would not normally get into a car with a stranger unless somehow duped or forced. Zhao recalls Yingying heeding news reports of women going missing, adding, "She is good at protecting herself."

Some reports suggested she may have called a ride-sharing service because she was running late, though investigators have not confirmed that. Local police said they received a separate report of someone posing as a police officer trying to lure women into his car, but have not said if it could be related.

The 5-foot-4, 110-pound Zhang, wearing a baseball cap and carrying a backpack, was seen on a surveillance video standing by the black Saturn Astra for a few minutes before getting in. Investigators say the driver appeared to be a white male.

Henry Chang-Yu Lee, a Connecticut-based criminal forensics expert who was born in China, said Zhang's case stands out because she disappeared in daylight hours. Abductions often occur at night and frequently outside bars and clubs, he said.

Illinois investigators are probably focused on identifying the owner of the car, trying to enhance surveillance video to read the license plate. They would also be combing Illinois sex-offender registration lists to see if anyone on it can be tied to the vehicle.

"But you are racing against time," he said. "If this car left Illinois and went to California or Texas, you'll have an even harder time finding her."

Zhang's father refuses to let himself think she won't be found alive. Addressing her in the interview, he said he won't leave Illinois during the search.

"I will wait for you," he said. "And we will definitely find you."