A police officer has helped thousands of families locate missing loved ones, Wang Ru reports.

Wang Binyan reunited with his missing grandson this summer, after 18 years. The 85-year-old from Hangzhou, Zhejiang province, choked with sobs while expressing his gratitude to Sui Yonghui, a 48-year-old policeman who helped bring his grandson home.

"Others had told me Sui would definitely find my grandson. And he really did," says Wang, who'd first heard about Sui from a Hangzhou Daily report in June.

Sui has contributed to investigations of missing people in his free time since 2014. He's hailed as the "commander-in-chief of searching for people" by local media.

Over the past five years, he has helped more than 3,500 families find their missing relatives, and the number keeps increasing.

In March, an old couple from Hangzhou asked Sui for help finding their intellectually disabled daughter, Hong Xiaoyan, who disappeared 20 years ago.

They had tried everything they could, and even opened a restaurant to expand their search with the help of their customers. But their attempts were in vain.

Sui says he was touched by the couple's persistence.

He uploaded Hong's photo to the internet for comparison and found three people whose appearances were most similar to hers. He then shared information about the three people on a police-cooperation platform. The police, in turn, informed him only one of the candidates wasn't local and had intellectual disabilities.

Sui collected her DNA and compared it with the couple's. The result showed she was their daughter.

When parents finally saw Hong, they threw themselves on their knees in front of Sui and refused to stand up for a long time.