Russia has released a Russian American imprisoned on treason charges that Washington has dismissed as ludicrous, but several other Americans remain in Russian custody.

Ksenia Karelina was arrested and convicted last year over a donation of about $52 to a charity aiding Ukraine.

Her release is the latest in a series of high-profile prisoner exchanges Russia and the United States carried out in the last three years.

Here is a look at other Americans who remain in Russian custody:

Stephen Hubbard

The Michigan native was convicted of fighting alongside Ukraine’s military as a mercenary against Russia and sentenced to six years and 10 months in October 2024. Prosecutors said in the closed trial that Hubbard had signed a contract with Ukraine’s military shortly after Russian troops invaded in February 2022 and that he fought with the Ukrainian side until being captured two months later. Hubbard, who was 72 at the time of his conviction, was the first American known to have been convicted of fighting for Ukraine in the conflict.

Travis Leake

The musician was convicted on drug charges and sentenced to 13 years in prison in July 2024. An Instagram page described him as the singer for the band Lovi Noch (Seize the Night). News reports said he is a former paratrooper with the U.S. military and had lived in Moscow since 2010.

Gordon Black

An Army staff sergeant, Black was convicted in June 2024 in Vladivostok of stealing and making threats against his girlfriend, and was sentenced to three years and nine months in prison. An appellate court this week reduced his sentence to three years and two months. He had flown to Russia from his post in South Korea without authorization and was arrested in May after his girlfriend accused him of stealing from her, according to U.S. and Russian authorities.

Robert Woodland

Woodland, a Russia-born U.S. citizen, was convicted of drug trafficking in July 2024 and sentenced to 12 1/2 years in prison. Russian media reported that his name matches a U.S. citizen interviewed in 2020 who said he was born in the Perm region in 1991 and adopted by an American couple at age 2. He said he traveled to Russia to find his mother and eventually met her on a TV show.

David Barnes

An engineer from Texas, Barnes was arrested in 2022 while visiting his sons in Russia, where their mother had taken them. His supporters say the woman made baseless claims of sexual abuse that already had been discredited by Texas investigators but a Russian court in February 2024 convicted him on those claims and sentenced him to 21 years in prison.

Robert Gilman

Identified in Russian media as a former U.S. Marine, Gilman was convicted of beating a police officer after being taken off of a train for causing a disturbance and handed a 3 1/2-year sentence in 2022. He later was convicted of attacking a prison inspector during a cell check, beating an investigator and assaulting a prison guard and was sentenced in October 2024 to seven years and one month in prison.

Eugene Spector

A Russian-born U.S. citizen, Spector was convicted of espionage and handed a 15-year prison term in December 2024. Spector, formerly an executive at a medical equipment company in Russia, was previously convicted of enabling bribes to a Russian government official and sentenced to 3 1/2 years in prison in September 2022.

Joseph Tater

Tater was arrested in August 2024 at an upscale Moscow hotel after an argument over documents. At a police station, he allegedly attacked an officer. He was convicted on hooliganism charges related to the hotel incident and handed a 15-day sentence, but is awaiting trial on assaulting a law officer. That carries a sentence of up to five years. He has denied the assault charges and argued that they stemmed from miscommunication. At a September court hearing, Tater claimed he came to Russia to seek political asylum and that he was being persecuted by the CIA. The state Tass news agency reported Sunday that a Moscow court ordered he be put into a psychiatric clinic for treatment.