China said Wednesday a staffer at the British consulate in Hong Kong has been given 15 days of administrative detention in the city of Shenzhen for violating regulations on public order.
The case has stoked fears among Hong Kong residents that Beijing is extending its judicial reach to Hong Kong, a semi-autonomous Chinese territory and former British colony.
“The relevant employee is a Hong Kong resident, not a British citizen,” Chinese Foreign Ministry spokesman Geng Shuang said at a daily briefing. “In other words, he is Chinese. This is purely the internal affairs of China.”
Geng said the man violated regulations on “Punishments in Public Order and Security Administration,” but gave no further details, adding that his case is “not a diplomatic issue.”
About two dozen people gathered Wednesday outside the British consulate in Hong Kong to demand the U.K. government step up efforts to secure the release of Simon Cheng Man-kit, a trade and investment officer at the consulate.
“Save Simon now!” the crowd chanted in front of a wall of missing person posters with pictures of Cheng.
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Max Chung, the event’s organizer and an acquaintance of Cheng’s, said Cheng travelled to the neighbouring mainland city of Shenzhen on a mainland travel permit for Hong Kong and Macao residents. He holds a British National Overseas passport, according to Chung. The travel document is issued by the U.K. to Hong Kong permanent residents.
Public order and security infractions are generally minor – for instance, fighting on the street – and result in administrative rather than criminal punishments. The maximum penalty for such transgressions is 15 days in detention.
The British foreign ministry has said it is “extremely concerned” about its staff member. Local media said he attended a business event in Shenzhen on Aug. 8 but never returned to neighbouring Hong Kong despite plans to do so the same day.
The seizure of consular staff of any status or rank is highly unusual. Despite Beijing’s declaration of a “golden era” in Sino-British ties, Sino-British relations have grown tense in recent months amid pro-democracy protests in Hong Kong, a former British colony.
“Regarding the series of words and deeds by the British side recently on Hong Kong-related issues, we have repeatedly lodged solemn complaints with the U.K.,” Geng said, adding that China urges the U.K. to “stop meddling in Hong Kong affairs.”
WATCH: Britain said it is concerned by reports that a consulate worker has been detained in China
Chung and other friends of Cheng said they believe he was detained at the high-speed railway station in West Kowloon, part of Hong Kong. The station stirred controversy ahead of its opening last September because passengers go through Chinese immigration and customs inside it.
Mainland law applies in the customs area, sparking concerns among Hong Kongers over the ability of mainland authorities to enforce Chinese law on Hong Kong soil. Some said this is a breach of the “one country, two systems” framework, which allows Hong Kong to largely run its own affairs until 2047.
Hong Kong Senior Police Superintendent Kong Wing-cheung said Tuesday that Hong Kong law enforcement agencies were not notified about the case by mainland Chinese authorities under a mutual notification arrangement set up for such cases.