Chinese state agents pose a daily threat to the UK's national security, said the head of MI5, Sir Ken McCallum, BNR reported.
He admitted that he was disappointed by the dismissal of a case against two Britons suspected of spying for Beijing.
In a speech at MI5 headquarters, the counter-intelligence chief said that his service had intervened operationally to thwart Chinese activity posing a national security threat in the past week.
Draw attention to the controversy surrounding the failure of a case related to alleged espionage for China in the UK, Ken McCallum said that the alleged activity had been thwarted by MI5 and that it was "disappointing when prosecutions fail".
The government and the Crown Prosecution Service face serious questions about the failure of the case. The prosecution dropped the case last month after deciding that the evidence did not show China was a threat to national security. But testimony from the UK’s deputy national security adviser, Matthew Colin, released late Wednesday, clearly shows that the Chinese are carrying out espionage operations against the country.