Brendt Christensen (middle) , the 28-year-old Illinois man charged with kidnapping Zhang Yingying, and the two images sketched by Lin Yuhui. [Photo/People's Daily Online]

FBI agents were amazed by a Chinese police officer who created the sketch of the man accused of kidnapping a Chinese scholar based on only grainy surveillance video clip, according to People's Daily Online.

Lin Yuhui, a police sketch artist from East China's Shandong province, said he was closely following the case of missing Zhang Yingying, a visiting scholar at the University of illinois at Urbana-Champaign. He was recommended to the US police to help with the investigation.

On June 17, Lin and three top Chinese video analysts received the video clip from US police.

They spent two days analyzing the video frame by frame as it was of low definition and was shot far away from where Zhang got into the suspect's car.

"This was not merely sketching. First you need to extract useful information from the video," Lin said.

Judging from the grainy profile in the clip, Lin thought the suspect was sturdy and of medium shape. He also managed to create general outline of the suspect's face.

Lin drew two images based on the limited information, which were then handed to US police through China's consulate-general in Chicago. Lin was told that the FBI agents were amazed by how he was able to sketch from such a grainy footage.

Lin is famous in China for his ability to spot clues and produce accurate sketches of suspects either from blurred photos or surveillance footages. His skills have solved many major cases.

Lin has sketched about 70,000 faces in his career, mainly people he has observed in public places such as railway stations. He also uses facial features that remain relatively unchanged over time to create portraits of missing children.

The FBI arrested the suspect, Brendt Christensen, a 28-year-old Illinois man on June 30, 21 days after Zhang went missing. However, the victim has not been found and is believed by authorities to be dead.