A Moscow court has placed a dual U.S.-Russian citizen, who is serving a prison sentence for bribery, in pre-trial detention on charges of espionage, according to court data published Thursday.Russian-born American Gene Spector faces 20 years in prison if convicted.

Few details outside the court ruling have been made public, as espionage cases are held behind closed doors since they deal with what authorities consider classified information.Spector wasdetained in 2020 on charges of “mediating” a bribe to the assistant of former Russian Deputy Prime Minister Arkady Dvorkovich in the form of vacations to Thailand and the Dominican Republic.

The assistant, Anastasia Alexeyeva, wassentenced to 12 years in prison.Spector pleaded guilty to the charges and reached a deal with investigators.

He was convicted in 2021, but the ruling was overturned and he was sentenced to 3.5 years in prison in September 2022.Spector was born and raised in Russia before moving to the United States where he obtained citizenship.

He was the general director of Russia's Medpolimerprom, a group of companies thatmakes plastic medical devices.Spector is listed among the inventors of a potentially effective cancer treatment agent, according to Russia’s intellectual property datacited by the RBC business news website.Spector still holds Russian citizenship,according to Radio Free Europe/Radio Liberty (RFE/RL).Several U.S.

citizens have in recent years been handed heavy sentences in Russia.

Washington accuses Moscow of seeking to use them as bargaining chips to obtain the release of Russians held in the United States.The United States has not said it considers Spector to be wrongfully detained,according to CBS News.AFP contributed reporting.