A British parliamentary researcher has been arrested on suspicion of spying for China in a major security breach at Westminster.
The man, in his late 20s, is believed to have links to a number of senior Tory MPs, including some with access to classified or highly sensitive information.
The suspect worked for a number of years with parliamentarians on international policy, including relations with Beijing, and held a parliamentary passport.
They include Tom Tugendhat, the Minister of Security, and Alicia Kearn, the chairman of the Foreign Affairs Committee.
He was arrested on March 13 along with another man on suspicion of espionage-related crimes.
Officers from the Metropolitan Police’s Counter Terrorism Command, which monitors espionage-related crimes, are investigating.
One of the men, in his 30s, was arrested in Oxfordshire on March 13, while the other, in his 20s, was arrested in Edinburgh, Scotland Yard said.
A senior Whitehall source told The Sunday Times: “This is a major escalation by China. We’ve never seen anything like this before.”
Security officials fear he may have been recruited during his stay in China.
Scotland Yard said: “Officers from the Metropolitan Police arrested two men on March 13 on suspicion of offenses under section one of the Official Secrets Act 1911.
“A man in his 30s was arrested at an address in Oxfordshire and a man in his 20s was arrested at an address in Edinburgh.
“Searches were also carried out at both the homes and a third address in east London. Both men were taken to a police station in south London and released on bail until a date in early October.”
The Telegraph has learned that Mr Tugendhat, a former chairman of the House of Commons Foreign Affairs Committee, has not spoken to the person since becoming security minister last September.
Ms Kearns declined to comment in a message on Twitter following the report.
She added: “While I recognize the public interest, we all have a duty to ensure that the work of the authorities is not compromised.”
A source close to Ms Kearns said: “It is no surprise that Alicia and Tom were targeted given their rock-solid record of changing the law on China – pushing the government to take tougher action against the Chinese Communist Party, from the Procurement Bill to Newport Wafer Fab, to Confucius Institutes, closing down illegal Chinese police stations and much more.
“This is what hostile states do: attack and try to undermine those they cannot silence. They have failed again.”
Ken McCallum, the head of MI5, has previously underlined that the Chinese Communist Party poses “the most game-changing strategic challenge” to Britain.
Further concerns have been raised that China is attacking Britain “frequently and aggressively”, according to the Commons intelligence and security committee, which published a report in July.
But the committee warned that government departments did not have the “resources, expertise or knowledge” to tackle the threat.
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