On Tuesday, British police announced that three Bulgarian nationals suspected of spying on behalf of Russia had been charged with "identity document offenses." The trio — two men and one woman — were arrested in February and have been in custody since, "held as part of a major national security investigation."

London’s Metropolitan Police confirmed five people had been arrested by counter-terrorism officers in February under the Official Secrets Act and three had since been charged with possession of false identity documents with improper intention.

A police statement named them as Orlin Roussev, 45, Biser Dzambazov, 42, and Katrin Ivanova, 31.

They appeared at London’s Old Bailey Court in July and were remanded in custody until a future date.

They have not yet entered pleas and are presently set to be tried at the Old Bailey in January.

The false identity documents included passports, identity cards, and related documents from the UK, Bulgaria, France, Italy, Spain, Croatia, Slovenia, Greece, and the Czech Republic.

Roussev, Dzambazov, and Ivanova are not new to the UK, having lived there for years and worked in a number of capacities. 

Mr Roussev has history of business dealings in Russia.

He moved to the UK in 2009 and spent three years working in a technical role in financial services.

His online LinkedIn profile states he later owned a business involved in signals intelligence, which involves the interception of communications or electronic signals.

Mr Roussev, whose most recent address is a seaside guesthouse in Great Yarmouth, also states he once acted as an adviser to the Bulgarian ministry of energy.

In Harrow, former neighbours described Mr Dzhambazov and Ms Ivanova as a couple.

Mr Dzhambazov is described as a driver for hospitals, and Ms Ivanova describes herself on her online LinkedIn profile as a laboratory assistant for a private health business.

The pair, who moved to the UK around a decade ago, ran a community organisation providing services to Bulgarian people, including familiarising them with the "culture and norms of British society".

According to Bulgarian state documents online, they also worked for electoral commissions in London which facilitate voting in Bulgarian elections by citizens living abroad.

Nor is this an isolated instance of British authorities uncovering Russian intelligence operations in the UK. 

In 2018, Russian operatives attempted to murder former double-agent Sergei Skripal and his daughter Yulia in Salisbury, Wiltshire, using the deadly nerve agent Novichok. The pair, as well as responding detective Nick Bailey, were treated in hospital and could have died.

Later that year, local woman Dawn Sturgess - who was unconnected to the Skripals - died after being exposed to the nerve agent, which had been left in Wiltshire in a perfume bottle.

In 2006, former Russian-intelligence officer Alexander Litvinenko was killed in London after being poisoned by assassins working for the Russian state.

This latest incident comes as Britain is ramping up its efforts to address external threats, recently passing a new National Security Bill aimed at updating its espionage laws and providing "law enforcement and intelligence agencies with new and updated tools to deter, detect and disrupt modern-day state threats."

At the time of its passage in July, the UK Government stated: 

This new act brings together vital new measures to protect the British public, modernise counter-espionage laws and address the evolving threat to our national security.

With this new legislation, the UK is now a harder target for those states who seek to conduct hostile acts against the UK, which include espionage, foreign interference (including in our political system), sabotage, and acts that endanger life, such as assassination.

The new powers will help ensure that the UK remains the hardest operating environment for malign activity undertaken by foreign actors.

Russia remains the most acute threat to the UK’s security, though we have seen interference from China including to communities here in the UK, and Iran has made concerted efforts to kill or kidnap British or UK-based individuals.

Expect to see more such arrests and charges coming down the pike.