(Reuters) - Russia has jailed three Jehovah's Witnesses for more than eight years each for alleged extremist activity, a spokesperson for the faith group said, the harshest sentences it has imposed yet on members of the organisation after hundreds of prosecutions.

New York-based spokesperson Jarrod Lopes said the verdicts were handed down in a case arising from a police raid on a cafe in 2018 where some 50 Jehovah's Witnesses were attending a social, not religious, event.

"All the facts considered during this trial clearly prove that I am being persecuted not for actual crimes, but for my religious views. The prosecution, without providing any evidence, is trying to promote the idea that I committed a crime," Lopes quoted one of the men, Nikolai Polevodov, as saying.

Polevodov was sentenced to 8.5 years, Vitaliy Zhuk to eight years and four months and Stanislav Kim to eight years and two months, Lopes said. Three women - Zhuk's wife Tatyana, Svetlana Sedova and Maya Karpushkina - received suspended sentences of five, five and four years respectively.

Religious life in Russia is dominated by the Russian Orthodox Church, which is championed by and loyal to President Vladimir Putin. Some Orthodox scholars view Jehovah's Witnesses, known for door-to-door preaching and refusing military service, as a "totalitarian sect".

Russia's Supreme Court designated the Jehovah's Witnesses as "extremist" in 2017, liquidating and banning their nearly 400 chapters across the country.

Since then, Lopes said, authorities have raided 2,102 homes of Jehovah's Witnesses, filed criminal charges against 811 men and women and sentenced 170 to prison terms, including 105 who were jailed for five years or more.

(Reporting by Mark Trevelyan; Editing by Christina Fincher)