A photo of Zhang Yingying released by the police.

UIUC police say a video shows 26-year-old Zhang Yingying of Fujian getting into the passanger side of a black Saturn Astra on the afternoon of June 9 after texting a prospective landlord that she was on her way to sign a lease. She has been missing ever since.

The FBI confirmed on Wednesday the case is being treated as kidnapping.

"The FBI has been involved, which is routine in missing persons cases," Patrick Wade, communications director of the UIUC Police Department, told China Daily. "But that they have identified the plate number is incorrect information, which gained traction on social media."

Police posted the video and photos of Zhang on their website (police.illinois.edu), asking people to view the images and offer whatever information they could.

Zhang had been living in the college town for a month. Police say she was last seen wearing a pink and white flannel shirt, blue jeans, white shoes and a gray hat with a white logo on the front. She was also carrying a dark blue backpack.

Apart from using the resources offered by partner law enforcement agencies and the FBI, UIUC Police also "continue to work with rideshare companies like Uber and Lyft, cellphone companies, check vehicle records and have pursued other information offered to us by members of the public", the website says.

The issue of student safety has come into focus since the incident was reported. Chinese overseas students say they avoid going out alone at night. If they have to, they ask others to accompany them. Students are also wary of unfamiliar places with few people and they avoid strangers.

Kris Wong, a student at Columbia University in New York City said he was concerned for college-age women.

"After the night's activities, we usually go home together, like taking an Uber. Especially for girls, we usually accompany them home after they get out of the car," said Wong.

Baron Yan, a junior at Purdue University, said, "For me if someone is way too friendly and I don't know the person, I tell them to have a nice day and walk away, because you never know what sort of motives they have, good or bad, I would rather not take the chance."

He offered a few tips for foreign students in America.

"They may think all Americans are good-hearted people because of how friendly they are and how willing they are to help. Though a majority of Americans are this, there are a few who have ulterior motives as to why they are friendly."

Wade emphasized the importance of 911. He suggests that even under normal circumstances, students should always be aware.

"We are deeply troubled anytime we believe a member of our campus community may be in danger, but we are very grateful for our community's support for Ms. Zhang," the police website reads.

Xiao Jiaqiao in New York contributed to this story.