Ex-police superintendent Bill Yuen, 65, and Peter Wai, 38 -- both dual Chinese-British nationals -- were found guilty of assisting a foreign intelligence service under Britain's national security laws following a weeks-long trial.

Wai, who worked for the UK's Border Force immigration and customs enforcement agency after previously serving in the British police and the Royal Navy, was also convicted of misconduct in a public office.

He had searched the interior ministry's computer system for people of interest to Hong Kong authorities.

The jury at London's Old Bailey court, which deliberated for nearly 24 hours, was discharged after failing to reach verdicts on a further foreign interference charge against each defendant.

Prosecutors promptly announced they would not seek a retrial and the duo were remanded into custody ahead of sentencing on a date to be set on May 15.

The court had heard how Wai had gathered intelligence on the orders of Yuen, who was a senior manager at the Hong Kong Economic Trade Office (HKETO), which represents Hong Kong's government in London.

- Politicians, campaigners -

The pair targeted Hong Kong dissidents and pro-democracy protesters living in Britain, with "special attention" also paid to politicians, including senior Conservative Iain Duncan Smith.

They undertook information gathering, surveillance and acts of deception, with one operation capturing photographs of prominent campaigner Nathan Law.

Their activities coincided with Hong Kong authorities publishing bounties of around pound100,000 ($136,000) for information helping to identify several UK-based activists, including Law, jurors heard.

Another protester told the jury of how Wai had threatened him with arrest for confronting a Hong Kong diplomat in London.

Messages on Yuen's phone showed surveillance of Law began as early as 2021, the prosecution said as it gave evidence.

The defendants' activities were exposed in May 2024 when police foiled an alleged bid to snatch a former Hong Kong resident from her flat in the northern county of Yorkshire, the court heard.

Wai, of Staines-upon-Thames, southwest of the capital -- who was known to associates as Fatboy -- and Yuen, of Hackney in east London, had both denied wrongdoing.

The case comes in the wake of tens of thousands of people, including democracy activists wanted by Chinese authorities, moving to Britain since Hong Kong enacted a draconian National Security Law in mid-2020.