Two men have been found guilty of spying for China after carrying out “shadow policing operations” on UK soil.

Retired Hong Kong Police superintendent Bill Yuen, 65, ran the operation from the Hong Kong Economic Trade Office (HKETO), in central London.

The Old Bailey heard he tasked Border Force officer Peter Wai, 38, and others, including ex-Royal Marine Matthew Trickett, on behalf of the Hong Kong intelligence service.

Prosecutors said they ran a surveillance and intimidation campaign against dissidents, who they called “cockroaches”, and tried to infiltrate the Hong Kong protest movement in the UK.

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, have both been found guilty 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.

The jury failed to agree on a verdict for a further charge of foreign interference over an alleged attempt to capture the personal assistant of a Chinese heiress in Pontefract, West Yorkshire, on 1 May 2024.

Wai was also convicted of misconduct in a public office by conducting searches of Home Office databases, which he had access to through his work, between 16 September 2022 and 2 May 2024.

Prosecutors are not seeking a retrial on the outstanding count and the pair were remanded in custody ahead of sentencing.

Worked at Heathrow Airport

Wai and Trickett were among 11 people arrested at the flat 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.

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.

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.

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 do some research regard details of their life”.

Bounties on their heads

In July 2023, the Hong Kong government offered a 1m HK dollar (£100,000) “bounty” for information about or for the capture of dissidents abroad, including Christopher Mung.

He 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”.

His 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.

“I didn’t realise that I was being targeted by the spies. I do believe they did exist, but I didn’t notice them,” Mr Mung said.

“I feel not safe, even though I’m not based in Hong Kong any more, even though I’m living in the UK.

“Therefore, I immediately installed CCTV in my house, Whenever I go out, I have to bring my personal alarm, I have to be alert about suspicious people approaching me, I have concerns about the safety of my family.”

Operation Hong Kong

Wai asked “best friend” Trickett to look at another high-profile Hong Kong democracy activist, Nathan Law, in a phone call on 16 August 2023 in what they dubbed Operation Hong Kong.

The ex-marine, who was also a private investigator, used Atlas, the government’s system for managing immigration and asylum applications, to produce a report.

Another operation was launched in November 2023, when Mr Law was giving a speech at the Oxford Union, to film him as he walked inside.

Mr Law said he had expected to be targeted but the revelation of the details and the people involved “comes with a certain level of worries and shock”.

“I’m quite surprised there are people in the system that are actively helping,” he told Sky News.

“It’s either they made a bad call in helping them, they didn’t know what they were doing. Or they genuinely feel like they can use their positions to retrieve this information and help a foreign government in doing those things. Both are terrible.”

Mr Law said he had expected to be targeted but the revelation of the details and the people involved “comes with a certain level of worries and shock”.

“I’m quite surprised there are people in the system that are actively helping,” he told Sky News.

“It’s either they made a bad call in helping them, they didn’t know what they were doing. Or they genuinely feel like they can use their positions to retrieve this information and help a foreign government in doing those things. Both are terrible.”

Operation Fox Hunt

The court heard Operation Fox Hunt is a continuing Chinese government programme to forcibly repatriate Chinese nationals wanted for alleged crimes.

Millionaire Tina Zou, a prominent Chinese businesswoman, who ran a family property development company in Beijing and Hong Kong accused her personal assistant, Monica Kwong, of siphoning off 144m HK dollars (£16.3m) before Ms Kwong fled the country in December 2023.

The court heard Wai used his job to access computer systems which found Ms Kwong, who denies the fraud, at a flat where she lived with her son in Pontefract.

A surveillance operation captured Ms Kwong’s arm through the window, before Ms Zou flew into Heathrow on April 30 2024 followed by two retired Hong Kong police officers.

Wai drove them north to Pontefract, where the team filmed on bodyworn cameras as they poked a surveillance camera under the door before Trickett, calling himself “Dave from maintenance” poured water, claiming there had been a leak.

The court heard police officers arrived to catch three men in the kitchen “rifling through the drawers”.

MI5 had placed a listening device in the flat, but it cut out when the men entered and apparently unplugged a light that was on a timer. Wai was found with a fake police chief superintendent card.

Ms Zhou was among those arrested but she and the two retired Hong Kong police officers were released and left the UK.

A police officer granted anonymity at the trial said: “At that time we didn’t have enough evidence for a charging decision. We ran out of time.”

‘I’m quite a boring guy’

Yuen, from Dalston, east London, told police, “I’m quite a boring guy”, and denied wrongdoing, saying he was only the office manager.

Wai, from Egham, Surrey, denied spying for China and said he was researching stories on the reality of life in London for Hong Kong expats for his lion dancing “master”.

He ran his own YouTube channel and told jurors his own lion dancing troupe had performed at 10 Downing Street.

They both denied assisting a foreign intelligence service between 20 December 2023 and 2 May 2024 and foreign interference on 1 May 2024 by forcing entry into Ms Kwong’s flat.

Wai also denied misconduct in a public office while working as a UK Border Force officer between 16 September 2022 and 2 May 2024.

Their convictions come after the controversial collapse of the prosecution of Christopher Cash and Christopher Berry, who were accused of passing information about MPs to China under the Official Secrets Act 1911, which they deny.

Mr Law said the successful prosecution “sends a very clear signal” and he hopes the prosecution will “have a deterrent effect”, but he is “still on high alert”.

“I really do hope that these people get a heavy sentencing because what they’re doing is a threat to democracy, is a threat to the system, and I think they should really face the consequences of their actions,” he said.