A photo of Zhang Yingying released by the police.

A Chinese student at the University of Illinois at Urbana-Champaign (UIUC) has not been seen for four days after she was last caught on security footage getting into a car on Friday. A massive search continues to be carried out by both police and at the grassroots level.

"We are doing everything we can to search for her, including the use of resources offered by our partner law enforcement agencies and the FBI," UIUC Police Department Chief Jeff Christensen said on Tuesday.

Zhang Yingying, 26, a visiting scholar from Fujian, had been in the US for about a month. She was conducting research at UIUC's department of natural resources and environmental sciences and living in university housing.

According to local media, Zhang had sent a text message last Friday confirming to a prospective landlord that she was on her way to Urbana to sign a lease on an apartment, but she never showed up.

Her last phone activity was at 1:30 pm the same day saying that she was running late and would not be there until around 2:10.

The last message on her phone was from the landlord delivered at 2:38 pm. "Hey Yingying! Just checking in to see if you're on your way."

There was no reply.

University police released security camera footage on Monday showing Zhang getting into a black Saturn Astra, which then continued north on Goodwin Avenue.

On UIUC's Reddit page, a user named "rosabel34" said the driver of a black sedan had approached a friend of hers on Friday as well and "she reported it to the police."

According to her friend's Facebook post, the man had a badge on a chain under his shirt and claimed to be an undercover police officer. He "asked me to come up to his car so he could ask me a few questions, which I refused to do," she wrote in her post.

"We have received many pieces of information and our detectives continue to work around the clock to develop new information," Chief Christensen said in his latest statement. "We continue to work with rideshare companies like Uber and Lyft, cellphone companies, check vehicle records and we have pursued other information offered to us by members of the public."

The Chinese Consulate General in Chicago has been in touch with police, the school and Zhang's parents, mobilizing all available resources to help find her. The consulate is also helping Zhang's parents get an emergency visa to come to the US.

Chinese student groups are also gathering whatever information they can about Zhang's disappearance.

"We're doing what we can, using all of our resources, and people here to help," Robin Huang of the Chinese Students and Scholars Association told Illinois homepage. net. "We really hope that we can speed things up and we really hope the girl is safe."

According to the Beijing News, Zhang's friends and schoolmates in China are also making an effort to raise awareness of Zhang's disappearance.

Investigators tried electronic positioning of Zhang's cellphone but it was shut down and it has been difficult to break through the phone's ID to locate it.

Zhang's boyfriend in China, Hou Xiaolin, is collecting information and disseminating it on as many platforms as he can, hoping to raise awareness of his girlfriend's plight.

"I wish the search process in the US could be faster," Hou said. "Everything is moving too slow."

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