Masked security agents and local police raided a worship service that was being by Jehovah's Witnesses in the central Russian city of Oryol, the latest in a series of raids following a Supreme Court ruling banning the denomination.
The religious group said that at least 15 officers, some masked and some heavily armed, halted the service on May 25, recorded names of attendees, seized cell phones and other electronics, and took written statements.
Several of the officers were from the Federal Security Service (FSB), Russia's primary security agency.
The group said that police also searched the homes of several Jehovah’s Witnesses in the city.
A Danish man, identified as Dennis Christensen, was also arrested during the raid.
A lawyer for the group, Yaroslav Sivulsky, told the Russian website Mediazone that Christensen was arrested only because he was reading the Bible along with other Jehovah's Witnesses.
A district court on May 26 ordered Chistensen held in custody while law enforcement conducted further investigation.
Jehovah's Witnesses have long been viewed with suspicion in Russia for their positions on military service, voting, and government authority in general.
Freedom of religion is formally guaranteed in Russia but legislation sets out Orthodox Christianity, Islam, Judaism, and Buddhism as the country's four traditional religions, and smaller denominations frequently face discrimination.
Last month, the Supreme Court labeled the Jehovah's Witnesses an extremist organization, ordering the seizure of its property in Russia and effectively banning worshipers from the country.
Since then, there have been a growing number of reports of worshipers being targeted for harassment.
A home and several cars belonging to a Jehovah's Witness outside of Moscow were vandalized in an arson attack on April 30.
"We believe that the closure of the Jehovah's Witnesses organization for extremism, the persecution of members of their communities, and the prohibition of their written texts all have no legitimate grounds and are an outright manifestation of religious discrimination," said the Sova Center, a nongovernmental organization that tracks extremism, xenophobia, racism and similar issues in Russia.