While Wall Street Journal reporter Evan Gershkovich, Russian American journalist Alsu Kurmasheva, former U.S. Marine Paul Whelan, and Russian British dissident Vladimir Kara-Murza were released in the biggest prisoner exchange since the Cold War on Thursday, another American still remains in Russian custody: Marc Fogel.

A history teacher from Pennsylvania who taught for nearly a decade at a Russian school, Fogel was arrested at a Moscow airport in August 2021 for possession of medical marijuana prescribed to treat spinal pain. In 2022, he was sentenced to a 14-year prison sentence at a Russian penal colony.

Here's what we know about Fogel and the attempts to obtain his release:

Who is Marc Fogel?

Fogel, in his early 60s, grew up in Butler, Pennsylvania. He attended Indiana University of Pennsylvania and went on to work teaching history courses at schools attended by children of U.S. diplomats. The work brought Fogel and his family across the globe as he taught in Colombia, Malaysia, Oman, Venezuela and Russia.

Starting in 2012, Marc Fogel and his wife, Jane, taught at the Anglo-American School in Moscow. In the summer of 2021, Fogel told his wife that he would retire after one more year teaching in Moscow, according to The Washington Post. It was upon their return to Moscow from a summer vacation that Fogel would be detained.

Why was Marc Fogel arrested?

On Aug. 14, 2021, Fogel was taken into custody at Moscow’s Sheremetyevo International Airport on a cannabis possession charge. Fogel and his family have said the cannabis was used to treat his chronic back pain.

His case would draw comparisons with that of WNBA All-Star Brittney Griner, who was arrested in February 2022 at a Russian airport for possession of vape cartridges containing cannabis oil. She pleaded guilty and was sentenced to nine years at a labor camp. In December of the same year, she was released in a prisoner exchange.

Unlike Griner, the U.S. Department of State has not declared Fogel as wrongfully detained, which has frustrated his family and lawmakers petitioning to get Fogel out of Russian custody.

Efforts to bring Fogel home

Since his arrest, Fogel's family have petitioned the U.S. government to free the longtime teacher and have been critical of the response they've received from the State Department and the Biden administration.

"I don't think the administration has helped us one bit," Fogel's mother, Malphine Fogel, told CBS Pittsburgh in early July. Days later, Malphine Fogel told The New York Post that former President Donald Trump promised to bring her son home when they spoke just before Trump took the stage at a rally in Butler and was wounded in an assassination attempt.

Also in July, Malphine Fogel filed a lawsuit against Secretary of State Antony Blinken and the U.S. Department of State for not designating Fogel as wrongfully detained, reported local television station WTAE.

The effort to free Fogel has also been taken up by lawmakers, especially Pennsylvania Rep. Mike Kelly.

Kelly as well as a group of bipartisan lawmakers in December 2023 wrote a letter to Blinken urging the government to classify Fogel as wrongfully detained, saying he meets at least six of the 11 established criteria for the classification.

Kelly and Pennsylvania representatives Chris Deluzio and Brendan Boyle also introduced the Marc Fogel Act, which would require the State Department to submit documents and communication to Congress about how it determines whether a U.S. citizen is being wrongfully.

On Thursday, U.S. Sens. Bob Casey and John Fetterman as well as Kelly and other lawmakers again asked the Biden administration to include Fogel in prisoner exchanges with Russia.

“As news of a potential prisoner exchange is being reported, we urge that any swap include Pennsylvania’s Marc Fogel, along with Paul Whelan and Evan Gershkovich,” they wrote in a letter. “Marc is a Pennsylvania teacher with severe health issues who has been unjustly imprisoned in a Russian prison for three years, and as the congressional members who represent Marc and his family, we have been pushing to bring Marc home as quickly as possible. As negotiations are ongoing with the Russian Federation, we respectfully request that any potential prisoner swap include Marc Fogel.”

Fogel's family 'heartbroken' and 'outraged' by prisoner swap

Fogel's family said they "are completely heartbroken and outraged" that Fogel was not among the Americans who was freed from Russian captivity on Thursday, according to a statement shared with USA TODAY through the family's lawyer, Sasha Phillips.

While the family sent well wishes to the families of Gershkovich and Whelan, they said the U.S. government's handling of Fogel's case has been a "glaring injustice," adding, "It is wrong, unfair, and not the America we know and love."

"Marc is not rich, a celebrity, or connected to powerful patrons. All he has is his family, led by his 95-year-old mother, Malphine, who is fighting for her son’s rights. This fight has been met not with support and understanding, but with stonewalling, double standards, and—today—abandoning Marc to die in prison for less than an ounce of medical marijuana prescribed to manage his severe decades-long spinal disease," the statement said.

"We demand immediate action to secure Marc’s release and call on President Biden, Secretary Blinken, Deputy Secretary Verma, and National Security Advisor Sullivan to say Marc Fogel’s name, designate him as wrongfully detained, and bring him home. The time for half-measures is over; we need results now."

Contributing: Reuters