A British parliamentary researcher has been arrested on suspicion of spying for China in a major security breach at Westminster.
The man, who is aged in his late twenties, is believed to be connected to a number of senior Tory MPs, including a number who have access to classified or highly sensitive information.
The suspect worked alongside MPs on international policy, including relations with Beijing, for a number of years and was a parliamentary pass holder.
They include Tom Tugendhat, the security minister, and Alicia Kearn, the chairwoman of the foreign affairs committee.
He was arrested along with another man on suspicion of espionage-related offences on March 13.
Officers from the Metropolitan Police’s counter terrorism command, which oversees espionage-related offences, are investigating.
One of the men, in his 30s, was detained in Oxfordshire on March 13, while the other, in his 20s, was arrested in Edinburgh, Scotland Yard said.
A senior Whitehall source told the The Sunday Times: “This is a major escalation by China. We have never seen anything like this before.”
Security officials fear he was recruited during his time living and working in China.
Scotland Yard said: “Officers from the Metropolitan Police arrested two men on March 13 on suspicion of offences under section one of the Official Secrets Act 1911.
“A man in his thirties was arrested at an address in Oxfordshire and a man in his twenties was arrested at an address in Edinburgh.
“Searches were also carried out at both the residential properties, as well as at a third address in east London. Both men were taken to a south London police station and were released on police bail until a date in early October.”
The Telegraph understands that Mr Tugendhat, a former chairman of the Commons foreign affairs committee, has not spoken to the individual since he became security minister last September.
Ms Kearns declined to comment in a post on Twitter in the wake of the report.
She added: “While I recognise the public interest, we all have a duty to ensure any work of the authorities is not jeopardised.”
A source close to Ms Kearns said: “It’s no surprise Alicia and Tom were targeted, given their cast iron record on changing legislation on China – pushing the Government to be tougher on the Chinese communist party from the Procurement Bill to Newport Wafer Fab, to Confucius institutes, getting illegal Chinese police stations closed and beyond.
“This is what hostile states do – target and seek to undermine those they can’t silence. They’ve failed again.”
Ken McCallum, the head of MI5, has previously underlined that the Chinese Communist Party poses “the most game-changing strategic challenge” to the UK.
Further concerns have been raised that China is targeting the UK “prolifically and aggressively”, according to the Commons intelligence and security committee, which published a report back 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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