Three Bulgarian citizens who were allegedly spying for Russia in the UK were arrested and charged in a major national security investigation months ago, but the story broke on Tuesday with a report published by the BBC.

The trio of alleged spies have been identified by the British broadcasting corporation as Orlin Roussev, 45, a resident of Great Yarmouth, Norfolk; Bizer Dzhambazov, 41, from Harrow, North West London; and Katrin Ivanova, 31, from the same Harrow address. Neighbors say the last two were apparently a couple.

They were detained in February under the Official Secrets Act by anti-terror detectives from London’s Metropolitan Police, which has responsibility for monitoring espionage. And they’ve been under arrest ever since.

They are accused of possessing false identity documents with “undue intent”. They also possessed passports and other documents from the United Kingdom, Bulgaria, France, Italy, Spain, Croatia, Slovenia, Greece, and the Czech Republic. The three defendants are due to go on trial at the Central Criminal Court of England and Wales, also known as the Old Bailey, in London in January.

Roussev moved to the UK in 2009, while Dzhambazov and Ivanova did the same more than a decade ago.