The San Uk Ling holding centre was constructed by the government of the then British Hong Kong in 1979 as an immigration detention facility. The increasing numbers of illegal immigrants attempting to sneak into Hong Kong from China had overburdened an existing detention facility at Ta Kwu Ling, which could only accommodate 60 people. The San Uk Ling facility, with a capacity of around 600, was built to hold illegal immigrants prior to their repatriation across the Chinese border, about a kilometre to the north. The holding centre was formally established in July 1979. Due to the huge increase in illegal immigration that year, the Hong Kong Auxiliary Police Force was mobilised, with several platoons posted to the San Uk Ling facility. It is located immediately south of Man Kam To Control Point, a border crossing which was, until 1985, the only vehicular road link between Hong Kong and China. It was Hong Kong's policy to return illegal immigrants to China within 24 hours of capture. Each day, those held at San Uk Ling were taken to the Man Kam To border crossing and handed over at 12:30 pm. Given the short duration that people were detained there, accommodation at San Uk Ling was rudimentary, with units divided only by steel fencing. By mid-1986, illegal immigration had declined, and the facility only held around 40 people on a daily basis. In late 1989 and early 1990, San Uk Ling Holding Centre was converted into a special facility designed to house Vietnamese refugees who were awaiting forced repatriation following their classification as non-refugees. Security was strengthened at this time, and the accommodation was improved. However, it is unclear if the facility was ever used for this purpose. The holding centre's five residential huts were reportedly fitted with air conditioners in April 1991. In early 1992, the maximum capacity of the facility was said to be 689. Following the Tiananmen Square massacre of 4 June 1989, San Uk Ling was used as a temporary shelter for movement leaders who were transported to Hong Kong during Operation Yellowbird. During the WTO Ministerial Conference in 2005, arrested militant Korean farmers were sent to San Uk Ling.
During the 2019–20 Hong Kong protests, some arrested protestors were sent to San Uk Ling as an overspill detention facility after 5 August 2019. On 11 August 2019 alone, 54 people who were arrested in Causeway Bay and Tsim Sha Tsui were sent there. While Yuen Long, Tuen Mun, Pat Heung, and Sheung Shui police stations being located closer to downtown Hong Kong and having some detainee capacity, San Uk Ling is more remote, making it difficult for arrested persons to contact outsiders. There are no closed-circuit televisions in the entrance and exit passages, meeting rooms and search rooms of San Uk Ling. In September 2019, 31 people detained in San Uk Ling were sent to North District Hospital, among whom six were seriously injured with bone fractures. One person was reportedly beaten to the point that his arm was connected to his torso only through skin. Others reportedly had their teeth beaten out, and some reportedly suffered intracerebral haemorrhages. There were also allegations of delays in sending the injured to the hospital, and deprivation of necessary medication. Some protesters taken to San Uk Ling also alleged sexual assault by officers there. Six justices of the peace who had wanted to visit San Uk Ling to investigate allegations of mistreatment there saw their request denied. The Police Public Relations Branch said that all the allegations against the centre were "unnamed", "unverified" and "untrue", that it had been nothing more than a standard detention facility, used in line with police regulations. They said that the centre had since 2 September not been used to hold arrested protesters, who would in future be sent to police stations across the city in case of mass arrests. The spokesman further added that the decision "has nothing to do with the groundless allegations of police of misconduct, and that it was a necessary step "to avoid any further public speculation and unnecessary remarks" as to its continued use.
Operations and characteristics
Unlike other prisons in Hong Kong, which are run by the Correctional Services Department, San Uk Ling is jointly operated by the Hong Kong Police Force and Immigration Department. As of 2019, the facility continues to be used to hold captured illegal immigrants prior to their repatriation. The facility falls under the purview of the Ta Kwu Ling Divisional Police Station. According to a 2019 statement by the Secretary for Security, San Uk Ling contains four cell blocks containing a total of 16 detention cells, which can collectively accommodate around 200 prisoners in total. The cells have stone beds, lighting, air conditioning, and toilets. The complex also has interview rooms. Contrary to popular belief, the detention centre is no longer located within the Frontier Closed Area, as the size of the closed area was reduced in recent years.
