A 65-year-old government contractor has been arrested under the Official Secrets Act by counter terror police.
The woman is contracted to carry out work for a government department and was arrested by Met's Counter Terrorism Command after receiving intelligence.
The contractor was arrested in north London on Wednesday (September 27) for an offence "contrary to Section 1 of the Official Secrets Act 1911".
The woman is being held in custody at a police station in south London an police are continuing to make enquiries.
A spokesman for the Met Police said: "Officers are also carrying out a search at an address in north London as part of the investigation.
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