Three people have been arrested on suspicion of spying for Russia, police have said.
The Metropolitan Police said two men aged 41 and 46 and a 35-year-old woman were arrested at two separate addresses in Grays, Essex, on suspicion of assisting the Russian intelligence service and taken to a police station in London.
The arrests followed a Counter Terrorism Policing investigation into suspected National Security Act offences, the force said.
Commander Dominic Murphy, head of the Counter Terrorism Command, said: “Through our recent national security casework, we’re seeing an increasing number of who we would describe as ‘proxies’ being recruited by foreign intelligence services.
“Indeed, two young British men are awaiting sentencing after they were recruited by the Wagner Group – effectively the Russian state – to carry out an arson at Ukrainian-linked warehouse.
“They are facing potentially lengthy custodial sentences, although, to be clear, today’s arrests are in no way connected to that investigation.
“But anyone who might be contacted by and tempted into carrying out criminal activity on behalf of a foreign state here in the UK should think again.
“This kind of activity will be investigated and anyone found to be involved can expect to be prosecuted and there are potentially very serious consequences for those who are convicted.”
All three have been bailed while the investigation continues.
