The prosecutor’s office identified one of the individuals as Anna N, a dual French-Russian national who has been under the surveillance of France’s DGSI domestic intelligence agency since January, on the belief she was gathering intelligence.

“In particular, she was suspected of having approached executives of various French companies to obtain information relating to French economic interests,” the prosecutor said in an emailed statement.

The prosecutor’s office did not identify the country the four people are suspected of spying for.

The others were identified as Vincent P and Bernard F, who were born in France and Vyacheslav P, a Russian national.

According to the prosecutor’s office, Anna N founded SOS Donbass, a France-based association which says on its website that it campaigns for closer ties between Europe and Russia, and the end of arms deliveries to Ukraine.

It often displays campaign posters in public places.

Anna faces up to 45 years in jail and 600,000 euros ($694,500.00) in fines for charges ranging from complicity to damage historic heritage sites, organised crime, spying and intelligence for a foreign power.

The others also face jail terms and fines on similar charges.