A Russian court sentenced Dennis Christensen, a Danish member of the Christian sect, the Jehovah's Witnesses, to six years in jail on Wednesday.
In 2017 Russia declared the Jehovah's Witnesses an extremist organisation. Critics are concerned for religious freedom in the country.
It has been suggested that Jehovah's Witnesses are under suspicion because they are seen as a Western influence, too independent from the Russian government, and activists are concerned that the crackdown is a test to see how Russians will react.
Al Jazeera's Rory Challands reports from Moscow.