SOFIA, Bulgaria (AP) — Bulgaria's foreign ministry said on Friday that a Russian diplomat had 72 hours to leave the country after prosecutors accused him of spying and gathering military information including the number of U.S. troops deployed to Bulgaria for military drills.

Foreign Minister Ekaterina Zaharieva has received a letter from the country's chief prosecutor saying that the Russian diplomat was engaged in espionage since 2017 but could not be charged because of his diplomatic immunity.

The deputy head of Russia’s embassy in Bulgaria has been notified of the diplomat's expulsion.

Local media identified the diplomat as Colonel Vasiliy Sazanovich, who had allegedly been coordinating Russia’s military intelligence spy network in Bulgaria.

The prosecutor’s office said in a statement that the diplomat had been collecting military information, including on U.S. troop numbers in the country.

The diplomat had allegedly been in contact with a Bulgarian citizen to whom he had offered money in exchange for classified information he had access to.

This is the fifth Russian diplomat this year that Bulgarian prosecutors have accused of spying and ordered expelled from the country.

Bulgaria, Moscow’s closest ally during the Cold War, is a member of NATO and the European Union but is still struggling to reduce its almost total dependence on Russian energy supplies.

The U.S. Embassy in Sofia issued a statement on Friday calling Bulgaria a “strong NATO ally and partner and has an unalienable right to defend its sovereignty.”

The embassy added that in recent weeks and months there have been “too many examples of Russian officials carrying out aggressive actions, from espionage in Bulgaria to poisoning opponents both at home and abroad.”