Hong Kong’s police chief and senior officials are mourning the death of a 31-year-old senior inspector, who died from injuries he suffered during an advanced selection assessment for the Special Duties Unit.

The officer lost consciousness after completing a diving segment of the SDU selection assessment off the coast of Lamma Island on Dec 4. He was rescued and rushed to Princess Margaret Hospital, where he underwent brain surgery. He died on Wednesday evening.

At the late-night press briefing at the hospital, Commissioner of Police Chow Yat-ming expressed his deepest condolences to the officer's family, and pledged that the Police Force will provide all necessary assistance and support.

Chow said the force is deeply saddened by the loss of a colleague and, prioritizing personnel safety, has immediately suspended the related selection procedures pending a comprehensive review to prevent similar incidents.

The late inspector joined the force in 2016 and was attached to the Police Tactical Unit Headquarters.

“He had all along shown great enthusiasm and passion for his work and was highly committed to his duties,” police said in a statement.

The case is being followed up by the Hong Kong Island Regional headquarters. A report will be submitted to the Coroner's Court, which will decide whether to hold an inquest into the cause of death.

In separate statements, Secretary for the Civil Service Ingrid Yeung Ho Poi-yan and Secretary for Security Chris Tang Ping-keung also expressed deep sorrow over the officer’s death.

The Special Duties Unit, dubbed the “Flying Tiger Squad”, is the Hong Kong Police Force’s elite tactical team responsible for counterterrorism, hostage rescue, underwater search and recovery, and armed crime response. Entry into the unit is voluntary, with a rigorous annual selection process that has a pass rate of less than 25 percent. Successful candidates also need to complete a demanding nine-month training program.