"The value of an individual lies in contributing to society, and we should work until the last moment of life, so that our life can be fulfilled," Guo Weimin, the former political commissar of the Criminal Investigation Brigade of the Fuzhou Public Security Bureau in Fujian province, would always say to those around him.

Since joining the police force in 1987 as a regular police officer, Guo gradually grew into a criminal investigation expert, participating in the resolution of over 300 major criminal cases, arresting over 1,000 suspects and breaking up several organized crime groups.

For 35 years, Guo was at the front line of criminal investigation. Even after being diagnosed with stomach cancer, during the most severe period of his illness, he lay on his sickbed tracking case progress over the phone, guiding investigation details. On March 15 last year, after his condition had deteriorated, he died at the age of 55.

He established a physical operation clue verification center and improved more than 20 long-term mechanisms such as the investigation and verification of clues for combating organized crime.

Guo's office contained over 50 volumes of work notes. They meticulously recorded 20 years of work details.

In 2008, Guo reopened an investigation into a cold case. It was a homicide committed years earlier, and a man surnamed Lin was implicated by the victim's family as the mastermind due to past conflicts. However, due to false information provided by Lin and other individuals involved in the case, Lin was acquitted and released.

Reinvestigating cold cases often faces the challenge of evidence loss and suspects being well prepared, making the process extremely difficult, said Lian Ping, an officer who was involved in the original investigation. "Without evidence, we could only try to break through via interrogation," he said.

The interrogation was not a simple question-and-answer session but a psychological battle. Guo didn't rush into the interrogation room but sat down to formulate a plan, he said.

"Before every interrogation, Guo would thoroughly investigate and organize details of the case, the suspect's interests, upbringing, family information and social circle, down to the smallest details, and then tailor his approach accordingly," Lian said.

During the interrogation, Guo, relying on thorough preparation and keen insight, captured a slight change in Lin's expression when he mentioned his lover, identified it as a breakthrough, and ultimately cracked the case, resulting in the arrest of Lin and other suspects.

Guo once told his colleagues, "No matter how difficult the investigation is, it can be overcome, and the case-related work must not be stalled."

In the eyes of the detectives who worked with him, he seemed tireless, never retreating and never allowing himself to stop.

As early as July 2022, Guo experienced abdominal discomfort, but he paid little attention to it. Concerned about his work, he didn't go to the hospital for a checkup until over a month later. In November, he was diagnosed with advanced stomach cancer.

Guo Xiaoling, his wife, said that seeing criminals punished and justice served was what Guo Weimin was most proud of.

"In 1993, when we just got married, it was the happiest time for me. My friends envied me due to his dedication to his police work and care for me," said Guo Xiaoling.

"Because of the nature of his work, I'd been living in constant fear for years. I had long-term insomnia, and I couldn't sleep at all when he didn't come home." Therefore, after every major operation, Guo Weimin would call his wife to let her know that he was safe so that she could sleep at ease.

Several years ago, Guo Xiaoling had thought about applying for early retirement, but Guo Weimin stopped her, and said that an individual's value lies in contributing to society.

He practiced what he preached, and devoted all his energy to his work, she said.

Guo was awarded a second-class merit citation, a commendation and a third-class merit citation four times. In June last year, Guo was posthumously awarded the title "Second-Class Hero Model of the National Public Security System" by the Ministry of Public Security.