SOFIA, Bulgaria (AP) — The United States on Saturday expressed strong backing for Bulgaria after it charged three Russian citizens with attempted murder and separately expelled two Russian diplomats accused of espionage.

In a statement, the U.S. Embassy in Sofia said that it “commends recent actions of the Bulgarian government to defend the country’s independence and sovereignty from malign influence.”

It also said that the government of Bulgaria has produced evidence of that Russia has supported “malign activities” in Bulgaria over a number of years and that the same Russian agents who were responsible for a poisoning case in Bulgaria were involved in similar activities across Europe.

On Friday, Bulgarian Foreign Minister Ekaterina Zaharieva said two Russian diplomats accused of spying will be declared persona non grata and expelled. They cannot be charged because they have diplomatic immunity.

Prosecutors claim the diplomats collected information about Bulgaria’s national elections and energy security.

A day earlier, Bulgarian authorities charged three Russian nationals with the attempted murder of the owner of a Bulgarian arms factory, his son and a company employee in 2015 using a phosphorus-like poison.

Prosecutors have issued European arrest warrants for the three.

“We support the long-term efforts of the agencies involved in investigating and exposing violations of Bulgarian law,” the U.S. Embassy said.

“Bulgaria is a strong NATO ally and EU partner and has an unalienable right to define its own future.”