A court in Russia has refused to release a Jehovah's Witness, Danish citizen Dennis Christensen, who was sentenced to six years in prison on extremism charges that have been condemned by rights groups in Russia and abroad.

The Jehovah’s Witnesses' website said that a court in Russia's western region of Kursk on October 26 refused to replace Christensen's unserved term with a fine despite the fact that the same court had approved such a move in June.

Christensen was arrested in May 2017 and sentenced in February 2019.

On June 23, the Lgov district court paroled Christensen after he served half of his sentence and ordered him to pay a fine of 400,000 rubles ($5,250) in place of serving the rest of his sentence.

However, that ruling was overturned by the Kursk Regional Court and sent for retrial after local prosecutors had appealed the parole, insisting that Christensen had violated prison rules.

The religious group's website said that the administration of the penal colony in the town of Lgov in September had labeled him a "malicious violator" of the penitentiary's regulations.

According to the website, Christensen was placed in solitary confinement three times as punishment for his refusal to carry out work, due to his medical condition.

Russia banned the Jehovah’s Witnesses in 2017 and declared the religious group an extremist organization.

According to human rights groups, hundreds of the religion's adherents are facing criminal cases in Russia, with dozens either imprisoned or awaiting trials.

In July, Human Rights Watch said in a statement that Russia “has absolutely nothing to gain from the pointless, cruel, and abusive persecution of Jehovah’s Witnesses,” urging the authorities to “immediately free Christensen and stop wasting time and resources on these prosecutions.”

In September 2019, the United States banned two high-ranking regional officers from Russia's Investigative Committee from entering the United States over the alleged torture of seven detainees who are Jehovah's Witnesses.