Three men have been charged under the National Security Act with assisting the Hong Kong intelligence service.

Chi Leung (Peter) Wai, 38, Matthew Trickett, 37, and Chung Biu Yuen, 63, have also been charged with foreign interference under the same Act, the Metropolitan Police said.

It follows an investigation led by officers from the Met’s Counter Terrorism Command in which 11 people in total were detained.

Eight men and a woman were arrested by officers on May 1 in the Yorkshire area, before a man was arrested in London and another man was arrested in the Yorkshire area the following day, the force said.

Wai, of Staines-upon-Thames, Trickett, of Maidenhead, and Yuen, of Hackney, were each charged with assisting a foreign intelligence service, contrary to section 3(1) and (9) of the National Security Act, and with foreign interference, contrary to section 13(2) and (7) of the same Act.

The seven men and one woman who were not charged were released from custody on or before May 10.

Commander Dominic Murphy, head of the Met’s Counter Terrorism Command, said: “This operation is not connected to a recently reported Counter Terrorism Policing investigation linked to Russia.

“A number of arrests were made and searches carried out across England as part of this investigation.

“While led from London, the Counter Terrorism Policing network has been crucial to disrupting this activity and we have worked closely with the Crown Prosecution Service since the start of the investigation.

“While these offences are concerning, I want to reassure the public that we do not believe there to be any wider threat to them.

“This investigation remains ongoing, but now that charges have been brought, I urge people not to speculate or comment further in relation to this case.”

The three men will appear in custody at Westminster Magistrates’ Court on Monday.