The British government has issued a warning to China after two spies were convicted of running campaigns of intimidation and surveillance on pro-democracy activists in the UK.
In response to the conviction of Bill Yuen and Peter Wai, the Chinese ambassador to the UK, Zheng Zeguang, was summoned by the Foreign Office.
The Foreign Secretary warned that the UK "will not tolerate any attempts by foreign states to intimidate, harass or harm individuals or communities in the UK" after the two men were convicted of spying on supposed opponents of the Beijing regime.
Wai, who was a Border Force officer and a retired Hong Kong Police superintendent, Yuen, were found guilty at the Old Bailey on Thursday of carrying out "shadow policing operations" on UK soil.
Yuen, 65, who ran the operation from the Hong Kong Economic Trade Office (HKETO) in central London, tasked Wai, 40, and others, including ex-Royal Marine Matthew Trickett, on behalf of the Hong Kong intelligence service.
Trickett, 37, took his own life in a park in Maidenhead on 19 May 2024, days after he first appeared in court alongside Yuen and Wai, a former Met police officer, who also volunteered as a City of London Police special constable and had previously served in the Royal Navy.
Yuen and Wai, who are dual Chinese and British nationals, were convicted of a charge of assisting a foreign intelligence service between 20 December 2023 and 2 May 2024 under the National Security Act after a two-month trial.
Foreign Secretary David Lammy summoned Ambassador Zeguang, following the end of a case "which resulted in convictions under the National Security Act to assist the Hong Kong authorities", an FCO spokesperson said on Saturday.
The statement added: "It was made clear that the UK will not tolerate any attempts by foreign states to intimidate, harass or harm individuals or communities in the UK, and that such activity constitutes a serious breach of the UK's sovereignty.
"We will continue to use the full range of tools available to protect our security and hold China to account for actions which undermine our safety and democratic values."
Wai and Trickett were among 11 people arrested following an MI5 operation.
Wai joined the Met in 2015 but resigned in 2019 during an investigation into his tax affairs before joining Border Force the following year, working at Heathrow Airport, where he had an airside pass.
Dissidents targeted
The court heard they also ran private security firm D5 Security, and that he met Yuen, who moved to London in 2015, in 2021 before they began to target dissidents in the UK.
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Wai flashed his police badge and threatened a protester with arrest after he confronted a Hong Kong official in London, while another activist from mainland China said she'd been followed from a demonstration and had her purchase payments tracked, the jury was told.
Wai told to 'take photos'
Yuen told Wai to pay "special attention to the government people or UK members of parliament, local councillors", who were supportive of the dissidents' cause, including Sir Iain Duncan Smith, chairman of the Inter-Parliamentary Alliance on China.
He was instructed to "take some photos" and research details of their lives.
Among others targeted were Nathan Law, a high-profile Hong Kong democracy activist, who was monitored when he spoke at the Oxford Union in November 2023.
Dissident Christopher Mung's name appeared in a note found on Trickett's phone alongside another high-profile activist Finn Lau, outlining a "sv [surveillance] task" in August 2023.
Mr Mung told Sky News two of his family members in Hong Kong were taken away for questioning, while he had his bank account and pension frozen, which had been "devastating for my future retirement plan".
(c) Sky News 2026: British government sends warning to China after two men caught spying on dissidents in the UK

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