Advisers to Russian President Vladimir Putin have questioned the legality of criminal cases opened against members of the Jehovah's Witnesses, saying law enforcement is misinterpreting a ruling last year by jailing people for collective bible reading and praying.

"It cannot but be a cause for concern because the criminal prosecutions and detentions have taken on a systemic character," the Russian Presidential Council for Civil Society and Human Rights said in a statement on June 21.

"The situation evokes associations with the Soviet period, when Jehovah's Witnesses suffered groundless repression because of their faith," the council said.

The council, which advises Putin but does not have policy-making powers, asked the General Prosecutor's office to protect the group's freedom of belief.

Putin will not necessarily take action based on the council's recommendations, but the issue is likely to be discussed during its next meeting with the president.

Russia’s Supreme Court in July 2017 upheld a ruling that the Jehovah’s Witnesses should be considered an extremist organization, effectively banning the denomination from the country.

The original ruling, issued in April 2017, was the first time an entire registered religious organization had been prohibited under Russian law.

Long viewed with suspicion in Russia for their positions on military service, voting, and government authority in general, the Jehovah’s Witnesses -- which claim some 170,000 adherents in Russia and 8 million worldwide -- are among several denominations that have come under increasing pressure in recent years.

Since the Supreme Court ruling, at least 19 members have been detained on criminal charges in Russia.

Yaroslav Sivulsky, a member of the European Association of Jehovah's Witnesses, said the council's intervention had given his group "a glimmer of optimism."

"We hope that common sense will prevail and that someone wise...will say that this has all gone too far," he said.

On June 18, the United States called on Russia to release dozens of people it says have been identified by rights groups as political

prisoners, including members of the Jehovah’s Witnesses who it said had been in pretrial detention for more than a year.

On June 19, some 60 Russian writers, historians, and activists signed an appeal calling on authorities to stop prosecuting the group.

With reporting by Reuters and RFE/RL's Russian Service