Located a few hundred metres away from the Man Kam To Control Point, a boundary crossing facility between Hong Kong and mainland China, the centre opened in July 1979 to house illegal immigrants prior to their repatriation.

The increasing number 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.

[2] 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.

[4] 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.

[6] 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.

[9] 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 the arrestees to contact outsiders.

[13] In response to lawmaker Tanya Chan’s enquires, John Lee, then Secretary for Security and later the Chief Executive, claimed amongst the 30 arrestees in San Uk Ling that required medical treatment, no one reported injury during the detention.

Poon Yung-wai, under the pseudonym "Kim Jong-un", published four posts in a Facebook group with more than 50,000 members in late September 2019, claiming to have learned about alleged sexual assaults in San Uk Ling from a police source.

Chief Judge of the High Court Jeremy Poon, said the offence warranted a jail sentence even for first-time offenders because it was very serious, considering it involved a targeted attack on law enforcement and a risk of breaching public order.

[23] IPCC examined San Uk Ling on 8 October and discussed with the Hong Kong Police representatives on the procedures for escorting and handling of the arrested persons.

After fully adopting the advice by the IPCC in its report, the Police installed surveillance cameras at the centre, added a fixed-line telephone, and upgraded its broadband service for better security and external communications.