The United States is calling on Russia to immediately release more than 150 individuals who human-rights groups have identified as unjustly imprisoned for their political or religious beliefs.
The Trump administration added its voice to a growing chorus of international human-rights activists pressing Moscow to release the prisoners while Russia is hosting the World Cup.
The State Department on Monday expressed "deep concern" that the Russian government has stepped up a Soviet-era practice of jailing dissidents and religious minorities, including Ukrainian filmmaker Oleh Sentsov and human rights activist Oyub Titiyev.
"We continue to raise these cases with the Russian government and press Russia to honor its international commitments, end this persecution and release these political prisoners," a State Department official told reporters Monday.
The United States is not intentionally timing its statement to coincide with Russia hosting the World Cup, according to the official.
"Some others have made a reference to the World Cup. We are not making that association," the State Department official said.
Russian authorities arrested Sentsov in Crimea in 2014 after Moscow seized the region. According to human rights groups, a Russian court in 2015 wrongfully convicted him of planning to commit terrorist acts and sentenced him to 20 years in prison.
Sentsov is one of four Ukrainians the State Department believes are unjustly jailed and who are currently on a hunger strike. The others are Stanislav Klykh, Oleksandr Shumkov, and Volodymyr Balukh.
"Time is running out and he may die for his views," writer Stephen King tweeted on Friday in a direct appeal for Sentsov.
Relatives of Sentsov had expressed hope that he might be freed in a prisoner exchange between Russia and Ukraine before the World Cup soccer tournament began, according to a report in the New York Times.
Titiyev, who heads the Chechen office of Human Rights Center Memorial, took on that leadership role after the killing of his colleague Natalia Estemirova in 2009. He has received numerous threats related to his work. Russian authorities arrested him in January on "bogus" drug charges in retaliation for exposing human-rights violations in Chechnya, according to the State Department.
The State Department officials said they have documented a "three-fold increase" since 2014 of Russia using its legal system to unjustly imprison dissidents and religious minorities. Russian authorities, the officials said, are transferring prisoners to remote and harsh prisons, including one located above the Arctic Circle.
U.S. officials cited the case of Dennis Christensen, who Russian authorities have detained without trial since May 2017, as well as five Church of Scientology leaders, held without trial for more a year, and more than a dozen Muslim followers of Turkish theologian Said Nursi.
The Commission on Security and Cooperation in Europe, also known as the U.S. Helsinki Commission, has identified Sentsov and several others as targeted for his political beliefs and wrongfully charged.
"We call on Russia to release all those identified as political or religious prisoners immediately and cease its use of the legal system to suppress dissent and peaceful religious practice," State Department spokeswoman Heather Nauert said in a statement. "The Russian people, like people everywhere, deserve equal treatment under the law and the ability to exercise their rights without fear of retribution."