8,307 missing and abducted children were found! What technology was used in the "Reunion" operation?

"Thank you for looking for me for so many years." On December 6, with the help of Shenzhen police, Sun Haiyang and his wife, the prototypes of the movie "Dear", met their son Sun Zhuo who had been abducted for 14 years. The three of them hugged each other tightly. The little boy who was "lulled" away by a toy car was finally reunited with his family.

Weibo screenshot

Since the beginning of this year, the Ministry of Public Security has deployed public security organs across the country to carry out the "Reunion" operation, making every effort to crack down on backlog cases of child trafficking, arrest suspects of child trafficking, and comprehensively search for missing and abducted children. As of November 30, public security organs have successfully cracked more than 290 backlog cases of child trafficking, arrested more than 690 suspects of child trafficking, and recovered a total of 8,307 missing and abducted children over the years, of which the longest time for missing and abducted persons to be separated from their relatives was 74 years. The "Reunion" operation has achieved remarkable results. So, what advanced scientific and technological means did the "Reunion" operation use in the search for relatives, and what role did these scientific and technological means play?

“Anti-trafficking DNA system” narrows the search for relatives

"Dad, Mom!" After a tearful call, Chen Jianxin embraced Hu Guoan and Kong Mulian and gently wiped the tears from their faces. Recently, in the meeting room of Tonggu County Public Security Bureau, a reunion across Jiangxi and Fujian provinces after 32 years moved every relative and police officer present.

Chen Jianxin's original name was Hu Sihua. In December 1989, Hu Sihua's father worked as a laborer at a construction site in Dajunji Town, Tonggu County, and the six-year-old Hu Sihua was playing nearby. At noon, Hu Sihua's father found that his son was missing. For many years, Hu Sihua's parents have never given up looking for their son, and have traveled to Yingtan, Yichun and other places to look for him.

Hu Sihua's disappearance has become a concern for the criminal police brigade of Tonggu County Public Security Bureau and the police officers of Dajun Town Police Station. He Ying, the former director of Dajun Town Police Station, said that he learned about the case as soon as he arrived in Dajun 10 years ago and went to Shaanxi Province to look for Hu Sihua based on the clues he collected at that time, but ultimately returned empty-handed.

For more than 30 years, Hu Sihua's case has always been a concern for the police. Every time the criminal technology is updated, the police will collect blood samples from Hu Sihua's parents and enter them into the database, and they have made many trips to Yichun, Nanchang, Shanghai and other places to look for them.

In January this year, the Ministry of Public Security organized public security organs across the country to carry out the "reunion" operation for abducted and missing children. The Criminal Police Brigade of Tonggu County Public Security Bureau carefully sorted out the basic information, collected blood samples from Hu Sihua's parents again for DNA data analysis, and entered the abducted and missing children information platform for comparison. Not long ago, the platform matched Chen Jianxin, a highly suspected person who worked in Taicang City, Jiangsu Province and was from Putian City, Fujian Province.

"On the one hand, our bureau immediately contacted Hu Sihua's parents for further verification and confirmation. On the other hand, we requested assistance from the Criminal Police Detachment of Yichun Public Security Bureau, contacted Chen Jianxin, and successfully collected his oral swab." Huang Xi, captain of the technical squadron of the Criminal Police Brigade of Tonggu County Public Security Bureau, said that after centralized DNA extraction, amplification, and electrophoresis of the blood samples of both parties, the DNA data was formally weighed, and then reviewed by the Yichun Public Security Bureau, Jiangxi Provincial Public Security Department, and the Ministry of Public Security, it was finally determined that Hu Sihua's parents were Chen Jianxin's biological parents.

If ten years ago, trying to find relatives in a vast crowd was like looking for a needle in a haystack, now, through DNA matching and other scientific and technological means, the search area can be narrowed down to a city, a county or even a more specific village. The difficulty is greatly reduced and the success rate is significantly improved.

Big data on portraits and free blood collection points have all played a role

Tong Bishan, deputy director of the Criminal Investigation Bureau of the Ministry of Public Security, said that the ongoing "Reunion" operation has many advantages:

In criminal technology, the technical means of finding missing and abducted persons are constantly enriched, especially my country's DNA testing technology and database construction are at the world's advanced level, becoming the most accurate method for finding and identifying relatives;

In terms of investigation organization, through the crackdown on unsolved homicide cases, a large amount of experience in many aspects has been accumulated. A group of experienced, professional and dedicated experts and talents have become the backbone of investigation and solving cases, laying a solid foundation for the "Reunion" operation;

In terms of action support, in the Internet era, information dissemination is faster and channels are more diverse. All sectors of society and the general public actively support and participate, gathering wisdom and strength for the "reunion" action;

In terms of cooperation mechanism, the cross-regional investigation cooperation mechanism of public security organs across the country has become increasingly perfect, and close cooperation and coordinated verification have become the norm, providing important guarantees for the implementation of the "Reunion" operation.

The reporter learned from the interview that for families where blood collection is difficult, the public security organs are also exploring the second-generation DNA sequencing technology, that is, expanding from paternity testing to kinship testing. For example, if the biological parents of a person suspected of being lost or abducted have passed away, or if it is inconvenient to draw blood due to old age or mobility problems, complex kinship relationships such as uncle-nephew, grandparent-grandchild, etc. will be identified through the second-generation DNA sequencing technology.

Family search technology is not just about DNA. Wang Xiang, an expert who participated in the "Reunion" operation criminal technology concentrated matching battle, said: The DNA data of the missing child has not been entered into the database, so it is impossible to produce a match or comparison. At this time, the photo of the child before he was lost is used to screen through big data of portraits to narrow the scope.

In recent years, portrait matching technology, like DNA matching technology, has been continuously iterating and developing, and its accuracy has been greatly improved. In the "reunion" operation, sometimes it is necessary to combine the two technologies to become the key to finding the abducted person.

It is understood that the Ministry of Public Security attaches great importance to the search for missing and abducted children, and has held four national video and telephone conferences to deploy and promote the "Reunion" operation; it has supervised a number of major child trafficking cases, organized elite forces to carry out special investigations, and made comprehensive use of new technologies and new methods to conduct in-depth research and analysis, and made every effort to tackle the backlog of cases; it has concentrated its superior resources and forces, and transferred more than 170 criminal technology experts from across the country to carry out the "Reunion" operation criminal technology concentrated comparison battle, assisted in the successful solving of 15 cases supervised by the Ministry, and recovered 3,672 missing and abducted children; it has given full play to scientific and technological support, deployed more than 3,000 free blood collection points across the country, and announced their addresses and contact numbers to the public, greatly facilitating the people to have blood drawn quickly and free of charge nearby; it has widely mobilized social forces to support and participate, deployed public security organs in various places to continue to carry out more than 2,600 family recognition activities, and continued to publicize the touching scenes of family reunions, creating a strong atmosphere of "everyone participates and the whole people support" in the fight against abduction and search for relatives.

In recent years, through the "Reunion" operation, the dreams of reunion of many abducted families have been fulfilled time and again with tears. This is a warm and mutual assistance between people, and an important manifestation of how science and technology can benefit society.

◎ Science and Technology Daily reporter Wei Yichen

Source: Science and Technology Daily

Editor: Zhang Qiqi

Review: Julie

Final review: Liu Haiying