The Romanian authorities claim the group sought to destabilize the constitutional order and withdraw Bucharest from NATO

The Romanian authorities have detained six people on charges of treason for allegedly trying to overthrow the government with the help of Russia. The development marks a dramatic escalation of tensions between Bucharest and Moscow after Russian diplomats were expelled from the country in connection with the case.

According to a unit called DIICOT that combats organized crime and Romania's spy agency, the SRI, a group called Vlad the Impaler Command sought to destabilize the country's constitutional order and withdraw it from NATO.

Vlad the Impaler was a medieval ruler of a region in present-day Romania, best known for his brutal military tactics and harsh punishment of enemies.

The group's members, among whom is a 101-year-old retired general, "actively requested support from Russian Federation Embassy officials," the SRI's statement reads.

According to DIICOT, the "organized criminal group" recruited followers online and also published video materials.

On Wednesday, Bucharest expelled two Russian diplomats in connection with the case. Moscow has denied any involvement in Romania's internal affairs and has vowed to retaliate for the expulsions.

Russian Foreign Ministry Spokeswoman Maria Zakharova has called out Bucharest's "obsession" with finding a "Russian trace" in its "internal political squabbles." She also accused the Romanian leadership of Russophobia and a persistent pursuit of escalation.

Last year, Romania accused Russia of interfering in its presidential elections, after Calin Georgescu, a critic of NATO and the EU and an opponent of aiding Ukraine, secured an unexpected first round victory in the national presidential election. The vote was almost immediately annulled by Romania's Constitutional Court, which cited alleged irregularities in the funding of his campaign.

Last week, as Georgescu was about to file his candidacy to run again for election, he was arrested and indicted on six criminal charges, including alleged "voter bribery," "promoting fascist, racist, or xenophobic ideologies," and incitement to actions against the constitutional order.

Georgescu has maintained his innocence and asked US President Donald Trump for help against what he described as a politically motivated campaign against him organized by the Romanian "deep state." 

Bloomberg reported in February that the Trump administration was pressuring Bucharest not to block Georgescu's candidacy for the presidency ahead of the new election in May.

READ MORE: Romanian presidential vote winner asks Trump for help from 'deep state'

Key Trump ally and adviser Elon Musk condemned Georgescu's arrest as "messed up." 

US Vice President J.D. Vance similarly criticized Romania while speaking at the Munich Security Conference in February, suggesting that certain "old entrenched interests" in the country were using "ugly, Soviet-era words like misinformation and disinformation" to prevent a politician with "an alternative viewpoint" from coming to power.