Two men who worked for Chinese intelligence in the UK have been jailed.

Chi Leung "Peter" Wai, 40, was sentenced to 10 years and Chung Biu "Bill" Yuen, 65, given an eight year term after being found guilty of assisting a foreign intelligence service, an offence under the National Security Act.

Wai, a Border Force officer who used his access to the Home Office computer system to track Hong Kong dissidents in the UK, was also convicted of misconduct in public office.

The judge told the men that their actions "threaten the sovereignty of the state" during sentencing remarks at the Old Bailey on Thursday.

Wai was a former UK police officer who began working as a Border Force officer at Heathrow Airport in December 2020.

He used his access to a vast database of information about foreign nationals in the UK to trace Hong Kongers who had fled pro-democracy crackdowns for his Chinese contacts.

Yuen, a former Hong Kong police officer who went on to work as the office manager of the Hong Kong Economic and Trade Office in London, became Wai's contact with Chinese authorities.

When Wai started working at Heathrow, he sent a message to the former chief superintendent of Hong Kong Police's Criminal Intelligence Bureau Eddie Ma, who still had links to the Chinese state.

"Will not let any cockroaches in," Wai wrote.

During a trial in May, the court heard that "special attention" was also paid to British politicians, such as Conservative MP Sir Iain Duncan Smith.

Wai, who holds both British and Hong Kong passports, has had many jobs - including as an officer with the Metropolitan Police from 2015 to 2019.

He was in the Royal Navy for eight years, and worked for a company providing security for events in Chinatown. Wai had also set up his own company, D5 Security.

After leaving the Met, he became a volunteer constable for City of London Police.

Wai also drew a fellow Border Force officer, an ex-Royal Marine called Matthew Trickett, into his surveillance of Hong Kong dissidents, the court heard.

Trickett was found dead in a suspected suicide soon after they were caught by counter-terrorism police. His inquest will be held in November.

In 2023, Hong Kong's chief executive John Lee Ka-chiu, its most senior politician, put bounties of HK$1m (around £100,000) on the heads of some pro-democracy campaigners.

In November 2023, Trickett was tasked by Wai to arrange for high-profile Hong Kong activist Nathan Law to be followed when he was speaking at the Oxford Union student society. He was one of the men with a HK$1m bounty on his head.

Head of the Counter Terrorism Division at the Crown Prosecution Service Bethan David said Wai and Yuen's conduct was "deliberate, coordinated and carried out with full knowledge of who it would benefit".

David added: "These convictions send a clear message that transnational repression, foreign interference, unauthorised surveillance, and attempts to operate outside the law will not be tolerated on British soil."

The jury could not agree on a charge against both men of foreign interference by forcing entry into the West Yorkshire home of an alleged fraud suspect originally from Hong Kong.