On 5/2, Chief Inspector O Khai Ninh, head of Team 1 of the Kowloon East Regional Crime Unit, chaired a press conference regarding a 37-year-old murder case that had just been solved.

Mai Dieu Cuong, the ringleader in the 1989 murder at Lung Ha Wan in Sai Kung district, was arrested after years of evading capture in Thailand and has now been extradited to Hong Kong.

As news of the arrest spread, O Khai Ninh also garnered unexpected attention when an old photo of her as a TVB reporter from approximately 20 years ago was recirculated by netizens, revealing her remarkable career transformation.

Career pivot

O Khai Ninh's career began around 2005 as a trainee reporter for TVB, covering football matches, community news, and criminal cases. She then worked as a reporter for Now News before becoming a news anchor for i-CABLE News Channel.

O Khai Ninh at the press conference for the "Alligator Pond" anti-fraud operation. Photo: HKCD

However, Khai Ninh did not continue on this path. Instead, she decided to apply to the Hong Kong Police Force. Candidates for the probationary inspector position must hold a university degree or equivalent qualification and must pass physical fitness tests, psychological evaluations, and multiple rounds of interviews. In 2011, Khai Ninh successfully passed these tests due to her strong personal capabilities.

After joining the police force, Khai Ninh was assigned to the Kowloon East Regional Crime Unit's Technology and Financial Crime Investigation Team. She leveraged her experience in information gathering, clue analysis, and logical deduction from her time as a reporter, gradually demonstrating her ability to solve cases. Subsequently, the Hong Kong Police appointed her as a senior inspector, responsible for recruitment in the human resources department.

In 10/2023, as Chief Inspector of the Technology and Financial Crime Investigation Team, Khai Ninh led an anti-fraud operation code-named "Alligator Pond," cracking 69 fraud cases and arresting 33 individuals. Among these were 40 phone scams targeting middle-aged and elderly people, with total defrauded funds exceeding 7 million HKD.

In 6/2024, Khai Ninh led an anti-money laundering operation, arresting 67 individuals involved in 108 victims and 73 million HKD.

In 12/2024, as Acting Regional Crime Investigation Director for Kowloon East, Khai Ninh commanded a large-scale anti-fraud operation code-named "Sword Array," mobilizing 518 police officers. Over three weeks, 154 individuals were arrested, with estimated funds involved reaching 289 million HKD.

O Khai Ninh (left) at the press conference on the arrest of Mai Dieu Cuong, solving a murder case from 37 years ago. Photo: Am730

O Khai Ninh at the press conference for the "Alligator Pond" anti-fraud operation. Photo: HKCD

These outstanding achievements earned Khai Ninh recognition within the police force. She was subsequently transferred to Team 1 of the Kowloon East Regional Crime Unit, serving as Chief Inspector, where she began to confront violent crime directly.

According to Xinmin Weekly, the requirements for promotion to Chief Inspector are extremely stringent, often demanding a master's degree or higher and successful completion of multiple assessment rounds. Women constitute approximately 18% of the security force, and fewer than 5% of inspectors in the major crime unit are women.

Solving a 37-year-old case

In the early morning of 31/8/1989, Lei Duc Tai, a 26-year-old waiter at a restaurant in Tsim Sha Tsui, was lured to Lung Ha Wan in Sai Kung by four men, including Mai Dieu Cuong, due to a personal dispute. Tai was beaten with an iron shovel for over 20 minutes, then tightly bound with nylon ropes and adhesive tape, and his head was covered with a plastic bag, causing suffocation. The four men hastily buried the victim's body on the beach. That afternoon, two swimmers accidentally discovered the body and reported it to the police.

Police quickly identified the four suspects. Two suspects were arrested in Hong Kong within two days of the discovery of the case. The third suspect was apprehended in mainland China in 2000, extradited to Hong Kong, and sentenced to life imprisonment for murder. However, the ringleader, Mai Dieu Cuong, fled Hong Kong the day after the murder, disappearing without a trace.

After escaping to Thailand, Cuong changed his name, opened a workshop and a restaurant in Samut Prakan province, started a new family, and had three children. After more than 30 years in hiding, Cuong's appearance had completely changed. This unresolved case became a persistent frustration for two generations of Hong Kong criminal police.

In 2025, O Khai Ninh took over the case.

According to Xinmin Weekly, Khai Ninh led her team in digitizing every original case file from 1989, creating a specialized database of clues. Concurrently, she meticulously reviewed social relationships, financial transactions, and monitored the activities of the four suspects' families. During the evidence classification process, she noted that police had recovered a faint fingerprint from the vehicle used by the suspects at the time of the crime. However, due to technological limitations at the time, it could not be successfully matched.

Subsequently, Khai Ninh collaborated with the Hong Kong Police Forensic Science Division and Interpol's Technical Division to use the latest fingerprint enhancement and 3D modeling technologies. This allowed them to reconstruct the fingerprint from the crime scene, extracting 12 key characteristic points. Through a match in Interpol's database, this fingerprint showed a high degree of correlation with the fingerprint of an illegal resident registered with Thai police – who was identified as Cuong.

In 12/2025, Thai police informed Hong Kong authorities that Cuong's whereabouts had been discovered in Bangkok. On 2/2, Thai police arrested Cuong at his home in Bangkok.

According to Hong Kong Commercial Daily, Cuong had no identification documents when arrested. Thai police confirmed his identity through fingerprint comparison. On 5/2, Cuong was extradited to Hong Kong and immediately arrested on murder charges.

At the press conference, Khai Ninh stated, "The Hong Kong Police have never given up on apprehending this suspect."

O Khai Ninh (left) at the press conference on the arrest of Mai Dieu Cuong, solving a murder case from 37 years ago. Photo: Am730

After her sudden rise to online prominence, Khai Ninh shared her career journey, asserting that as long as one possesses capability, there is always an opportunity for success whenever one wishes to change professions.

Khai Ninh's story is not an isolated incident. Over the years, Hong Kong's media industry has "supplied" a significant number of talents to the police force, with nearly 10 individuals from TVB and i-Cable News alone.

Luu Trieu Bang, a veteran TVB reporter, joined the police force in 2002 and is currently a commanding officer in Tai Po district. Luu Gia Nghiep, a former i-Cable News MC and former member of the Hong Kong Judo team, became a probationary inspector in 2008 and has since been promoted to chief inspector. Du Dich Dong, a former TVB MC, is currently a senior inspector.

Besides Khai Ninh, the Hong Kong police force boasts other outstanding female figures, such as Trieu Hue Hien, Deputy Commissioner of Police in 2017, and Trinh Le Ky, Assistant Commissioner of Police. The proportion of female inspectors in the Hong Kong police force has increased from 13% in 1990 to nearly 30%, while the proportion of female directors has risen from 2,8% to 24,5%.

Tue Anh (according to Global People, Xinmin Weekly)