The Sun has reported that the suspect, who is in his 40s, is accused of spying in Great Britain for Russian president Vladimir Putin.
The man was arrested on Monday (June 13) morning under section one of the Official Secrets Act as he tried to depart on an outbound flight from the UK.
Section one relates to offences to espionage, sabotage and related crimes.
A spokesperson from the Metropolitan Police said: “We can confirm that officers from the Met’s Counter Terrorism Command arrested a man in his 40s at Gatwick Airport on Monday 13 June on suspicion of offences under section 1 of the Official Secrets Act 1911.
“He has been taken to a London police station, where he currently remains in police custody. Enquiries continue.”
A source told The Sun: "The suspect is believed to have been in the UK spying on behalf of the Putin regime.
“He was kept under observation and arrested as he arrived at Gatwick to try and fly out of the country.’’
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